Soybean variety XR28K10

ABSTRACT

A novel soybean variety, designated XR28K10 is provided. Also provided are the seeds of soybean variety XR28K10, cells from soybean variety XR28K10, plants of soybean XR28K10, and plant parts of soybean variety XR28K10. Methods provided include producing a soybean plant by crossing soybean variety XR28K10 with another soybean plant, methods for introgressing a transgenic, mutant trait, and/or native trait into soybean variety XR28K10, methods for producing other soybean varieties or plant parts derived from soybean variety XR28K10. Soybean seed, cells, plants, germplasm, breeding lines, varieties, and plant parts produced by these methods and/or derived from soybean variety XR28K10 are further provided.

FIELD OF INVENTION

This invention relates generally to the field of soybean breeding, specifically relating to a soybean variety designated XR28K10.

BACKGROUND

The present invention relates to a new and distinctive soybean variety designated XR28K10, which has been the result of years of careful breeding and selection in a comprehensive soybean breeding program. There are numerous steps in the development of any novel, desirable soybean variety. Plant breeding begins with the analysis and definition of problems and weaknesses of the current germplasm, the establishment of program goals, and the definition of specific breeding objectives. The next step is selection of germplasm that possess the traits to meet the program goals. The breeder's goal is to combine in a single variety an improved combination of desirable traits from the parental germplasm. These important traits may include but are not limited to: higher seed yield, resistance to diseases and insects, tolerance to drought and heat, altered fatty acid profile, abiotic stress tolerance, improvements in compositional traits and better agronomic characteristics.

These product development processes, which lead to the final step of marketing and distribution, can take from six to twelve years from the time the first cross is made until the finished seed is delivered to the farmer for planting. Therefore, development of new varieties is a time-consuming process that requires precise planning, efficient use of resources, and a minimum of changes in direction.

Soybean (Glycine max), is an important and valuable field crop. Thus, a continuing goal of soybean breeders is to develop stable, high yielding soybean varieties that are agronomically sound. The reasons for this goal are to maximize the amount of grain produced on the land used and to supply food for both animals and humans. To accomplish this goal, the soybean breeder must select and develop soybean plants that have the traits that result in superior varieties.

The soybean is the world's leading source of vegetable oil and protein meal. The oil extracted from soybeans is used for cooking oil, margarine, and salad dressings. Soybean oil is composed of saturated, monounsaturated and polyunsaturated fatty acids. It has a typical composition of 11% palmitic, 4% stearic, 25% oleic, 50% linoleic and 9% linolenic fatty acid content (“Economic Implications of Modified Soybean Traits Summary Report”, Iowa Soybean Promotion Board & American Soybean Association Special Report 92S, May 1990). Changes in fatty acid composition for improved oxidative stability and nutrition are also important traits. Industrial uses for processed soybean oil include ingredients for paints, plastics, fibers, detergents, cosmetics, and lubricants. Soybean oil may be split, inter-esterified, sulfurized, epoxidized, polymerized, ethoxylated, or cleaved. Designing and producing soybean oil derivatives with improved functionality, oliochemistry, is a rapidly growing field. The typical mixture of triglycerides is usually split and separated into pure fatty acids, which are then combined with petroleum-derived alcohols or acids, nitrogen, sulfonates, chlorine, or with fatty alcohols derived from fats and oils.

Soybean is also used as a food source for both animals and humans. Soybean is widely used as a source of protein for animal feeds for poultry, swine and cattle. During processing of whole soybeans, the fibrous hull is removed and the oil is extracted. The remaining soybean meal is a combination of carbohydrates and approximately 50% protein.

For human consumption soybean meal is made into soybean flour which is processed to protein concentrates used for meat extenders or specialty pet foods. Production of edible protein ingredients from soybean offers a healthy, less expensive replacement for animal protein in meats as well as dairy-type products.

SUMMARY

A novel soybean variety, designated XR28K10 is provided. Also provided are the seeds of soybean variety XR28K10, cells from soybean variety XR28K10, plants of soybean XR28K10, and plant parts of soybean variety XR28K10. Methods provided include producing a soybean plant by crossing soybean variety XR28K10 with another soybean plant, methods for introgressing a transgenic, a mutant trait, and/or a native trait into soybean variety XR28K10, methods for producing other soybean varieties or plant parts derived from soybean variety XR28K10. Soybean seed, cells, plants, germplasm, breeding lines, varieties, and plant parts produced by these methods and/or derived from soybean variety XR28K10 are further provided.

DEFINITIONS

Certain definitions used in the specification are provided below. Also in the examples which follow, a number of terms are used. In order to provide a clear and consistent understanding of the specification and claims, the following definitions are provided:

AERIAL WEB BLIGHT. Aerial blight is caused by the fungus Rhizoctonia solani, which can also cause seedling blight and root rot. Stems, flowers, pods, petioles, and leaves are susceptible to formation of lesions. Tolerance to Aerial Web Blight is rated on a scale of 1 to 9, with a score of 1 being very susceptible, ranging up to a score of 9 being tolerant.

ALLELE. Any of one or more alternative forms of a genetic sequence. In a diploid cell or organism, the two alleles of a given sequence typically occupy corresponding loci on a pair of homologous chromosomes.

ANTHESIS. The time of a flower's opening.

APHID ANTIBIOSIS. Aphid antibiosis is the ability of a variety to reduce the survival, growth, or reproduction of aphids that feed on it. Screening scores are based on the ability of the plant to decrease the rate of aphid reproduction. Plants are compared to resistant and susceptible check plants grown in the same experiment. Scores of 1=susceptible, 3=below average, 5=average, 7=above average, and 9=exceptional tolerance.

BACKCROSSING. Process in which a breeder crosses a donor parent variety possessing a desired trait or traits to a recurrent parent variety (which is agronomically superior but lacks the desired level or presence of one or more traits) and then crosses the resultant progeny back to the recurrent parent one or more times. Backcrossing can be used to introduce one or more desired traits from one genetic background into another background that is lacking the desired traits.

BREEDING. The genetic manipulation of living organisms.

BU/A=Bushels per Acre. The seed yield in bushels/acre is the actual yield of the grain at harvest.

Brown Stem Rot=BSR=Brown Stem Rot Tolerance. This is a visual disease score from 1 to 9 comparing all genotypes in a given test. The score is based on leaf symptoms of yellowing, necrosis and on inner stem rotting caused by Phialophora gregata. A score of 1 indicates severe symptoms of leaf yellowing and necrosis. Increasing visual scores from 2 to 8 indicate additional levels of tolerance, while a score of 9 indicates no symptoms.

BSRLF=Brown Stem Rot disease rating based solely on leaf disease symptoms. This is a visual disease score from 1 to 9 comparing all genotypes in a given test. A score of 1 indicates severe leaf yellowing and necrosis Increasing visual scores from 2 to 8 indicate additional levels of tolerance, while a score of 9 indicates no leaf symptoms

BSRSTM=Brown Stem Rot disease rating based solely on stem disease symptoms. This is a visual disease score from 1 to 9 comparing all genotypes in a given test. A score of 1 indicates severe necrosis on the inner stem tissues. Increasing visual scores from 2 to 8 indicate additional levels of tolerance, while a score of 9 indicates no inner stem symptoms

CELL. Cell as used herein includes a plant cell, whether isolated, in tissue culture, or incorporated in a plant or plant part.

CHARCOAL ROT DISEASE. A fungal disease caused by Macrophomina phaseolina that is enhanced by hot and dry conditions, especially during reproductive growth stages. Tolerance score is based on observations of the comparative ability to tolerate drought and limit losses from charcoal rot infection among various soybean varieties. A score of 1 indicates severe charcoal rot on the roots and dark microsclerotia on the lower stem. Increasing visual scores from 2 to 8 indicate additional levels of tolerance, while a score of 9 indicates no lower stem and/or root rot.

CHLORIDE SENSITIVITY. This is a measure of the chloride concentration in the plant tissue from 1 to 9. The higher the score the lower the concentration of chloride in the tissue measured.

CW or Canopy Width. This is a visual observation of the canopy width which is scored from 1 to 9 comparing all genotypes in a given test. A score of 1=very narrow, while a score of 9=very bushy.

CNKR or Stem Canker Tolerance. This is a visual disease score from 1 to 9 comparing all genotypes in a given field test. The score is based upon field reaction to the disease. A score of 1 indicates susceptibility to the disease, whereas a score of 9 indicates the line is resistant to the disease.

STEM CANKER GENE. Resistance based on a specific gene that infers specific resistance or susceptibility to a specific race of Stem Canker. The score is based upon a reaction of tooth pick inoculation with a race of stem canker. A score of 1 indicates severe stem canker lesions, similar to a known susceptible check variety, whereas a score of 9 indicates no disease symptoms, consistent with a known resistant check variety

COTYLEDON. A cotyledon is a type of seed leaf. The cotyledon contains the food storage tissues of the seed.

CROSS-POLLINATION. Fertilization by the union of two gametes from different plants.

DIPLOID. A cell or organism having two sets of chromosomes.

ELITE VARIETY. A variety that is sufficiently homozygous and homogeneous to be used for commercial grain production. An elite variety may also be used in further breeding.

EMBRYO. The embryo is the small plant contained within a mature seed.

EMGSC=Field Emergence=Emergence Score. A score based upon speed and strength of emergence at sub-optimal conditions. Rating is done at the unifoliate to first trifoliate stages of growth. A score using a 1 to 9 scale is given, with 1 being the poorest and 9 the best. Scores of 1, 2, and 3=degrees of unacceptable stands; slow growth and poor plant health. Scores of 4, 5, 6=degrees of less than optimal stands; moderate growth and plant health. Scores of 7, 8, 9,=degrees of optimal stands; vigorous growth and plant health.

FEC=Iron-deficiency Chlorosis=Iron Chlorosis. Plants are scored 1 to 9 based on visual observations. A score of 1 indicates the plants are dead or dying from iron-deficiency chlorosis, a score of 5 means plants have intermediate health with some leaf yellowing, and a score of 9 means no stunting of the plants or yellowing of the leaves. Plots are usually scored in mid July.

FECL=Iron-deficiency Chlorosis—Late. Plants are scored 1 to 9 based on visual observations. A score of 1 indicates the plants are dead or dying from iron-deficiency chlorosis, a score of 5 means plants have intermediate health with some leaf yellowing and a score of 9 means no stunting of the plants or yellowing of the leaves. Plots are scored later in the growing season, typically around mid August.

FEY or Frogeye Leaf Spot. This is a visual fungal disease score from 1 to 9 comparing all genotypes in a given experiment. The score is based upon the number and size of leaf lesions. A score of 1 indicates severe leaf necrosis spotting, whereas a score of 9 indicates no lesions.

FLOWER COLOR. Data values include: P=purple and W=white.

GENE SILENCING. The interruption or suppression of the expression of a nucleic acid sequence at the level of transcription or translation.

GENOTYPE. Refers to the genetic constitution of a cell or organism.

PLANT HABIT. This refers to the physical appearance of a plant. It can be determinate (Det), semi-determinate, intermediate, or indeterminate (Ind). In soybeans, indeterminate varieties are those in which stem growth is not limited by formation of a reproductive structure (i.e., flowers, pods and seeds) and hence growth continues throughout flowering and during part of pod filling. The main stem will develop and set pods over a prolonged period under favorable conditions. In soybeans, determinate varieties are those in which stem growth ceases at flowering time. Most flowers develop simultaneously, and most pods fill at approximately the same time. The terms semi-determinate and intermediate are also used to describe plant habit and are defined in Bernard, R. L. 1972. “Two genes affecting stem termination in soybeans.” Crop Science 12:235-239; Woodworth, C. M. 1932. “Genetics and breeding in the improvement of the soybean.” Bull. Agric. Exp. Stn. (Illinois) 384:297-404; Woodworth, C. M. 1933. “Genetics of the soybean.” J. Am. Soc. Agron. 25:36-51.

HAPLOID. A cell or organism having one set of the two sets of chromosomes in a diploid cell or organism.

HERBRES=Herbicide Resistance. This indicates that the plant is more tolerant to the herbicide shown than the level of herbicide tolerance exhibited by wild type plants. A designation of RR indicates tolerance to glyphosate and a designation of STS indicates tolerance to sulfonylurea herbicides.

HGT=Plant Height. Plant height is taken from the top of the soil to the top pod of the plant and is measured in inches.

HILUM. This refers to the scar left on the seed which marks the place where the seed was attached to the pod prior to harvest. Hila Color data values include: BR=brown; TN=tan; Y=yellow; BL=black; IB=Imperfect Black; BF=buff.

HYPL=Hypocotyl length=Hypocotyl elongation. This score indicates the ability of the seed to emerge when planted 3″ deep in sand pots and with a controlled temperature of 25° C. The number of plants that emerge each day are counted. Based on this data, each genotype is given a score from 1 to 9 based on its rate of emergence and the percent of emergence. A score of 1 indicates a very poor rate and percent of emergence, an intermediate score of 5 indicates average ratings, and a score of 9 indicates an excellent rate and percent of emergence

HYPOCOTYL. A hypocotyl is the portion of an embryo or seedling between the cotyledons and the root.

LDGSEV=Lodging Resistance=Harvest Standability. Lodging is rated on a scale of 1 to 9. A score of 1 indicates plants that are laying on the ground, a score of 5 indicates plants are leaning at a 45° angle in relation to the ground, and a score of 9 indicates erect plants.

LEAFLETS. These are part of the plant shoot, and they manufacture food for the plant by the process of photosynthesis.

LINKAGE. Refers to a phenomenon wherein alleles on the same chromosome tend to segregate together more often than expected by chance if their transmission was independent.

LINKAGE DISEQUILIBRIUM. Refers to a phenomenon wherein alleles tend to remain together in linkage groups when segregating from parents to offspring, with a greater frequency than expected from their individual frequencies.

LLC=Oil with three percent or less linolenic acid is classified as low linolenic oil. Linolenic acid is one of the five most abundant fatty acids in soybean seeds. It is measured by gas chromatography and is reported as a percent of the total oil content.

LLE=Linoleic Acid Percent. Linoleic acid is one of the five most abundant fatty acids in soybean seeds. It is measured by gas chromatography and is reported as a percent of the total oil content.

LLN=Linolenic Acid Percent. Linolenic acid is one of the five most abundant fatty acids in soybean seeds. It is measured by gas chromatography and is reported as a percent of the total oil content.

LOCUS. A defined segment of DNA.

PRM Predicted Relative Maturity or Relative Maturity. Soybean maturities are divided into relative maturity groups (00, 0, I, II, III, IV . . . X or 00, 0, 1, 2, 3, . . . 10). Within a maturity group are sub-groups. A sub-group is a tenth of a relative maturity group (for example 1.3 would indicate a group 1 and subgroup 3).

MAT ABS=Absolute Maturity. This term is defined as the length of time from planting to complete physiological development (maturity). The period from planting until maturity is reached is measured in days, usually in comparison to one or more standard varieties. Plants are considered mature when 95% of the pods have reached their mature color.

MATURITY GROUP. This refers to an agreed-on industry division of groups of varieties, based on the zones in which they are adapted primarily according to day length or latitude. They consist of very long day length varieties (Groups 000, 00, 0), and extend to very short day length varieties (Groups VII, VIII, IX, X).

Narrow rows. Term indicates 7″ and 15″ row spacing.

NEI DISTANCE. A quantitative measure of percent similarity between two lines. Nei's distance between lines A and B can be defined as 1−((2*number alleles in common)/(number alleles in A+number alleles in B)). For example, if lines A and B are the same for 95 out of 100 alleles, the Nei distance would be 0.05. If lines A and B are the same for 98 out of 100 alleles, the Nei distance would be 0.02. Free software for calculating Nei distance is available on the internet at multiple locations such as, for example, at: evolution.genetics.washington.edu/phylip.html. See Nei & Li (1979) Proc Natl Acad Sci USA 76:5269-5273, which is incorporated by reference for this purpose.

NUCLEIC ACID. An acidic, chainlike biological macromolecule consisting of multiple repeat units of phosphoric acid, sugar and purine and pyrimidine bases.

OIL=Oil Percent. Soybean seeds contain a considerable amount of oil. Oil is measured by NIR spectrophotometry, and is reported as a percentage basis.

Oil/Meal TYPE: Designates varieties specially developed with the following oil traits: HLC=High Oleic oil; LLC=Low Linolenic (3% linolenic content); ULC=Ultra Low Linolenic oil (1% linolenic oil content); HSC=High Sucrose meal; LPA=Low Phytic Acid; LST=Low Saturate oil; Blank=Conventional variety/oil composition.

OLC=Oleic Acid Percent. Oleic acid is one of the five most abundant fatty acids in soybean seeds. It is measured by gas chromatography and is reported as a percent of the total oil content.

PEDIGREE DISTANCE. Relationship among generations based on their ancestral links as evidenced in pedigrees. May be measured by the distance of the pedigree from a given starting point in the ancestry.

PERCENT IDENTITY. Percent identity as used herein refers to the comparison of the homozygous alleles of two soybean varieties. Percent identity is determined by comparing a statistically significant number of the homozygous alleles of two developed varieties. For example, a percent identity of 90% between soybean variety 1 and soybean variety 2 means that the two varieties have the same allele at 90% of the loci used in the comparison.

PERCENT SIMILARITY. Percent similarity as used herein refers to the comparison of the homozygous alleles of a soybean variety such as XR28K10 with another plant, and if the homozygous allele of XR28K10 matches at least one of the alleles from the other plant then they are scored as similar. Percent similarity is determined by comparing a statistically significant number of loci and recording the number of loci with similar alleles as a percentage. A percent similarity of 90% between XR28K10 and another plant means that XR28K10 matches at least one of the alleles of the other plant at 90% of the loci used in the comparison.

PLANT. As used herein, the term “plant” includes reference to an immature or mature whole plant, including a plant from which seed or grain or anthers have been removed. Seed or embryo that will produce the plant is also considered to be the plant.

PLANT PARTS. As used herein, the term “plant parts” includes leaves, stems, roots, root tips, anthers, seed, grain, embryo, pollen, ovules, flowers, cotyledon, hypocotyl, pod, flower, shoot, stalk, tissue, cells and the like.

PLM or Palmitic Acid Percent. Palmitic acid is one of the five most abundant fatty acids in soybean seeds. It is measured by gas chromatography and is reported as a percent of the total oil content.

PMG infested soils: soils containing Phytophthora sojae.

POD. This refers to the fruit of a soybean plant. It consists of the hull or shell (pericarp) and the soybean seeds. Pod Color data values include: BR=brown; TN=tan.

PRT or Phytophthora Field Tolerance. Tolerance to Phytophthora root rot is rated on a scale of 1 to 9, with a score of 1 indicating the plants have no tolerance to Phytophthora, ranging to a score of 9 being the best or highest tolerance.

PHYTOPHTHORA RESISTANCE GENE (Rps). Various Phytophthora resistance genes are known and include: Rps1a=resistance to races 1-2, 10-11, 13-8, 24; Rps1c=resistance to races 1-3, 6-11, 13, 15, 17, 21, 23, 24, 26, 28-30, 32, 34, 36; Rps1k=resistance to races 1-11, 13-15, 17, 18, 21-24, 26, 36, 37; Rps6=resistance to races 1-4, 10, 12, 14-16, 18-21, 25, 28, 33-35; and (−) indicates no specific gene for resistance is detected.

PRMMAT or Predicted Relative Maturity. Soybean maturities are divided into relative maturity groups. In the United States the most common maturity groups are 00 through VIII. Within maturity groups 00 through V are sub-groups. A sub-group is a tenth of a relative maturity group. Within narrow comparisons, the difference of a tenth of a relative maturity group equates very roughly to a day difference in maturity at harvest.

PRO or Protein Percent. Soybean seeds contain a considerable amount of protein. Protein is generally measured by NIR spectrophotometry, and is reported on a dry weight basis.

PUBESCENCE. This refers to a covering of very fine hairs closely arranged on the leaves, stems and pods of the soybean plant. Pubescence Color-data values include: L=Light Tawny; T=Tawny; G=Gray.

R160 or Palmitic Acid percentage. Percentage of palmitic acid as determined using methods described in Reske, et al., Triacylglycerol Composition and Structure in Genetically Modified Sunflower and Soybean Oils. JAOCS 74:8, 989-998 (1997), which is incorporated by reference for this purpose.

R180 or Stearic acid percentage. Percentage of Stearic acid as determined using methods described in Reske, et al., Triacylglycerol Composition and Structure in Genetically Modified Sunflower and Soybean Oils.

JAOCS 74:8, 989-998 (1997), which is incorporated by reference for this purpose.

R181 or Oleic acid percentage. Percentage of oleic acid as determined using methods described in Reske, et al., Triacylglycerol Composition and Structure in Genetically Modified Sunflower and Soybean Oils. JAOCS 74:8, 989-998 (1997), which is incorporated by reference for this purpose.

R182 or Linoleic acid percentage. Percentage of linoleic acid as determined using methods described in Reske, et al., Triacylglycerol Composition and Structure in Genetically Modified Sunflower and Soybean Oils. JAOCS 74:8, 989-998 (1997), which is incorporated by reference for this purpose.

R183 or Linolenic acid percentage. Percentage of linolenic acid as determined using methods described in Reske, et al., Triacylglycerol Composition and Structure in Genetically Modified Sunflower and Soybean Oils. JAOCS 74:8, 989-998 (1997), which is incorporated by reference for this purpose.

RESISTANCE. Synonymous with tolerance. The ability of a plant to withstand exposure to an insect, disease, herbicide, environmental stress, or other condition. A resistant plant variety will be able to better withstand the insect, disease pathogen, herbicide, environmental stress, or other condition as compared to a non-resistant or wild-type variety.

RKI or Root-knot Nematode, Southern. This is a visual disease score from 1 to 9 comparing all genotypes in a given experiment. The score is determined by digging plants to visually score the roots for presence or absence of galling. A score of 1 indicates large severe galling covering most of the root system which results in pre-mature death from decomposition of the root system. A score of 9 indicates that there is no galling of the roots.

RKA or Root-knot Nematode, Peanut. This is a visual disease score from 1 to 9 comparing all genotypes in a given experiment. The score is determined by digging plants to score the roots for presence or absence of galling. A score of 1 indicates large severe galling covering most of the root system which results in pre-mature death from decomposition of the root system. A score of 9 indicates that there is no galling of the roots.

SCN=Soybean Cyst Nematode Resistance=Cyst Nematode Resistance. The score is based on resistance to a particular race of soybean cyst nematode, such as race 1, 2, 3, 5 or 14. Scores are from 1 to 9 and indicate visual observations of resistance as compared to other genotypes in the test. A score of 1 indicates nematodes are able to infect the plant and cause yield loss, while a score of 9 indicates SCN resistance.

SCN Resistance Source. There are three typical sources of genetic resistance to SCN: PI88788, PI548402 (also known as Peking), and PI437654 (also known as Hartwig).

SCN infected soils: soils containing soybean cyst nematode.

SD VIG or Seedling Vigor. The score is based on the speed of emergence of the plants within a plot relative to other plots within an experiment. A score of 1 indicates no plants have expanded first leaves, while a score of 9 indicates that 90% of plants growing have expanded first leaves.

SDS or Sudden Death Syndrome is caused by the fungal pathogen Fusarium solani f.sp. glycines. Tolerance to Sudden Death Syndrome is rated on a scale of 1 to 9, with a score of 1 being very susceptible ranging up to a score of 9 being tolerant.

SEED COAT LUSTER. Data values include D=dull; S=shiny.

SEED SIZE SCORE. This is a measure of the seed size from 1 to 9. The higher the score the smaller the seed size measured.

SPLB=S/LB=Seeds per Pound. Soybean seeds vary in seed size, therefore, the number of seeds required to make up one pound also varies. This affects the pounds of seed required to plant a given area, and can also impact end uses.

SHATTR or Shattering. This refers to the amount of pod dehiscence prior to harvest. Pod dehiscence involves seeds falling from the pods to the soil. This is a visual score from 1 to 9 comparing all genotypes within a given test. A score of 1 indicates 100% of the pods are opened, while a score of 9 means pods have not opened and no seeds have fallen out.

SHOOTS. These are a portion of the body of the plant. They consist of stems, petioles and leaves.

STC or Stearic Acid Percent. Stearic acid is one of the five most abundant fatty acids in soybean seeds. It is measured by gas chromatography and is reported as a percent of the total oil content.

SUBLINE. Although XR28K10 contains substantially fixed genetics, and is phenotypically uniform and with no off-types expected, there still remains a small proportion of segregating loci either within individuals or within the population as a whole.

WHMD or White Mold Tolerance. This is a fungal disease caused by Sclerotinia sclerotiorum that creates mycelial growth and death of plants. Tolerance to white mold is scored from 1 to 9 by visually comparing all genotypes in a given test. A score of 1 indicates complete death of the experimental unit while a score of 9 indicates no symptoms.

VARIETY. A substantially homozygous soybean line and minor modifications thereof that retain the overall genetics of the soybean line including but not limited to a subline, a locus conversion, a mutation, a transgenic, or a somaclonal variant.

High yield environments. Areas which lack normal stress, typically having sufficient rainfall, water drainage, low disease pressure, and low weed pressure

Tough environments. Areas which have stress challenges, opposite of a high yield environment

DETAILED DESCRIPTION

The variety has shown uniformity and stability for all traits, as described in the following variety description information. It has been self-pollinated a sufficient number of generations, with careful attention to uniformity of plant type to ensure a sufficient level of homozygosity and phenotypic stability. The variety has been increased with continued observation for uniformity. No variant traits have been observed or are expected.

A variety description of Soybean variety XR28K10 is provided in Table 1. Traits reported are average values for all locations and years or samples measured.

Soybean variety XR28K10, being substantially homozygous, can be reproduced by planting seeds of the variety, growing the resulting soybean plants under self-pollinating or sib-pollinating conditions, and harvesting the resulting seed, using techniques familiar to the agricultural arts.

Performance Examples of XR28K10

As shown in Table 2, the traits and characteristics of soybean variety XR28K10 are given in paired comparisons with other varieties. Traits reported are mean values for all locations and years where paired comparison data was obtained.

Genetic Marker Profile

In addition to phenotypic observations, a plant can also be identified by its genotype. The genotype of a plant can be characterized through a genetic marker profile which can identify plants of the same variety or a related variety, or which can be used to determine or validate a pedigree. Genetic marker profiles can be obtained by techniques such as restriction fragment length polymorphisms (RFLPs), randomly amplified polymorphic DNAs (RAPDs), arbitrarily primed polymerase chain reaction (AP-PCR), DNA amplification fingerprinting (DAF), sequence characterized amplified regions (SCARs), amplified fragment length polymorphisms (AFLPs), simple sequence repeats (SSRs) also referred to as microsatellites, or single nucleotide polymorphisms (SNPs). For example, see Cregan et al, “An Integrated Genetic Linkage Map of the Soybean Genome” Crop Science 39:1464-1490 (1999), and Berry et al., Assessing Probability of Ancestry Using Simple Sequence Repeat Profiles: Applications to Maize Inbred Lines and Soybean Varieties” Genetics 165:331-342 (2003), each of which are incorporated by reference herein in their entirety.

Particular markers used for these purposes are not limited to any particular set of markers, but are envisioned to include any type of marker and marker profile which provides a means of distinguishing varieties. One method of comparison is to use only homozygous loci for XR28K10. For example, one set of publicly available markers which could be used to screen and identify variety XR28K10 is disclosed in Table 3.

Primers and PCR protocols for assaying these and other markers are disclosed in Soybase (sponsored by the USDA Agricultural Research Service and Iowa State University) located at the world wide web at 129.186.26.94/SSR.html. In addition to being used for identification of soybean variety XR28K10 and plant parts and plant cells of variety XR28K10, the genetic profile may be used to identify a soybean plant produced through the use of XR28K10 or to verify a pedigree for progeny plants produced through the use of XR28K10. The genetic marker profile is also useful in breeding and developing backcross conversions.

The present invention comprises a soybean plant characterized by molecular and physiological data obtained from the representative sample of said variety deposited with the ATCC. Further provided is a soybean plant formed by the combination of the disclosed soybean plant or plant cell with another soybean plant or cell and comprising the homozygous alleles of the variety.

Means of performing genetic marker profiles using SSR polymorphisms are well known in the art. A marker system based on SSRs can be highly informative in linkage analysis relative to other marker systems in that multiple alleles may be present. Another advantage of this type of marker is that, through use of flanking primers, detection of SSRs can be achieved, for example, by using the polymerase chain reaction (PCR), thereby eliminating the need for labor-intensive Southern hybridization. PCR detection is done using two oligonucleotide primers flanking the polymorphic segment of repetitive DNA to amplify the SSR region.

Following amplification, markers can be scored by electrophoresis of the amplification products. Scoring of marker genotype is based on the size of the amplified fragment, which correlates to the number of base pairs of the fragment. While variation in the primer used or in laboratory procedures can affect the reported fragment size, relative values should remain constant regardless of the specific primer or laboratory used. When comparing varieties it is preferable if all SSR profiles are performed in the same lab.

Primers used are publicly available and may be found in Soybase or Cregan (1999 Crop Science 39:1464-1490). See also, WO 99/31964 Nucleotide Polymorphisms in Soybean, U.S. Pat. No. 6,162,967 Positional Cloning of Soybean Cyst Nematode Resistance Genes, and U.S. Pat. No. 7,288,386 Soybean Sudden Death Syndrome Resistant Soybeans and Methods of Breeding and Identifying Resistant Plants, the disclosures of which are incorporated herein by reference.

The SSR profile of soybean plant XR28K10 can be used to identify plants comprising XR28K10 as a parent, since such plants will comprise the same homozygous alleles as XR28K10. Because the soybean variety is essentially homozygous at all relevant loci, most loci should have only one type of allele present. In contrast, a genetic marker profile of an F1 progeny should be the sum of those parents, e.g., if one parent was homozygous for allele x at a particular locus, and the other parent homozygous for allele y at that locus, then the F1 progeny will be xy (heterozygous) at that locus. Subsequent generations of progeny produced by selection and breeding are expected to be of genotype xx (homozygous), yy (homozygous), or xy (heterozygous) for that locus position. When the F1 plant is selfed or sibbed for successive filial generations, the locus should be either x or y for that position.

In addition, plants and plant parts substantially benefiting from the use of XR28K10 in their development, such as XR28K10 comprising a backcross conversion, transgene, or genetic sterility factor, may be identified by having a molecular marker profile with a high percent identity to XR28K10. Such a percent identity might be 90%, 95%, 96%, 97%, 98%, 99%, 99.5% or 99.9% identical to XR28K10.

The SSR profile of XR28K10 also can be used to identify essentially derived varieties and other progeny varieties developed from the use of XR28K10, as well as cells and other plant parts thereof. Such plants may be developed using the markers identified in WO 00/31964, U.S. Pat. No. 6,162,967 and U.S. Pat. No. 7,288,386. Progeny plants and plant parts produced using XR28K10 may be identified by having a molecular marker profile of at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 99.5% genetic contribution from soybean variety, as measured by either percent identity or percent similarity. Such progeny may be further characterized as being within a pedigree distance of XR28K10, such as within 1, 2, 3, 4 or 5 or less cross-pollinations to a soybean plant other than XR28K10, or a plant that has XR28K10 as a progenitor. Unique molecular profiles may be identified with other molecular tools such as SNPs and RFLPs.

Introduction of a New Trait or Locus into XR28K10

Variety XR28K10 represents a new base genetic variety into which a new locus or trait may be introgressed. Direct transformation and backcrossing represent two important methods that can be used to accomplish such an introgression.

A backcross conversion of XR28K10 occurs when DNA sequences are introduced through backcrossing (Hallauer et al. in Corn and Corn Improvement, Sprague and Dudley, Third Ed. 1998), with XR28K10 utilized as the recurrent parent. Both naturally occurring and transgenic DNA sequences may be introduced through backcrossing techniques. A backcross conversion may produce a plant with a trait or locus conversion in at least two or more backcrosses, including at least 2 backcrosses, at least 3 backcrosses, at least 4 backcrosses, at least 5 backcrosses, or more. Molecular marker assisted breeding or selection may be utilized to reduce the number of backcrosses necessary to achieve the backcross conversion. For example, see Openshaw, S. J. et al., Marker-assisted Selection in Backcross Breeding. In: Proceedings Symposium of the Analysis of Molecular Data, August 1994, Crop Science Society of America, Corvallis, Oreg., where it is demonstrated that a backcross conversion can be made in as few as two backcrosses.

The complexity of the backcross conversion method depends on the type of trait being transferred (a single gene or closely linked genes compared to unlinked genes), the level of expression of the trait, the type of inheritance (cytoplasmic or nuclear), dominant or recessive trait expression, and the types of parents included in the cross. It is understood by those of ordinary skill in the art that for single gene traits that are relatively easy to classify, the backcross method is effective and relatively easy to manage. (See Hallauer et al. in Corn and Corn Improvement, Sprague and Dudley, Third Ed. 1998). Desired traits that may be transferred through backcross conversion include, but are not limited to, sterility (nuclear and cytoplasmic), fertility restoration, nutritional enhancements, drought tolerance, nitrogen utilization, altered fatty acid profile, low phytate, industrial enhancements, disease resistance (bacterial, fungal or viral), insect resistance, and herbicide resistance. In addition, a recombination site itself, such as an FRT site, Lox site or other site specific integration site, may be inserted by backcrossing and utilized for direct insertion of one or more genes of interest into a specific plant variety. A single locus may contain several transgenes, such as a transgene for disease resistance that also contains a transgene for herbicide resistance. The gene for herbicide resistance may be used as a selectable marker and/or as a phenotypic trait. A single locus conversion of site specific integration system allows for the integration of multiple genes at a known recombination site in the genome.

The backcross conversion may result from either the transfer of a dominant allele or a recessive allele. Selection of progeny containing the trait of interest is accomplished by direct selection for a trait associated with a dominant allele. Transgenes transferred via backcrossing typically function as a dominant single gene trait and are relatively easy to classify. Selection of progeny for a trait that is transferred via a recessive allele requires growing and selfing the first backcross generation to determine which plants carry the recessive alleles. Recessive traits may require additional progeny testing in successive backcross generations to determine the presence of the locus of interest. The last backcross generation is usually selfed to give pure breeding progeny for the trait(s) being transferred, although a backcross conversion with a stably introgressed trait may also be maintained by further backcrossing to the recurrent parent with subsequent selection for the trait.

Along with selection for the trait of interest, progeny are selected for the phenotype of the recurrent parent. The backcross is a form of inbreeding, and the features of the recurrent parent are automatically recovered after successive backcrosses. Poehlman suggests from one to four or more backcrosses, but as noted above, the number of backcrosses necessary can be reduced with the use of molecular markers (Poehlman et al (1995) Breeding Field Crops, 4th Ed., Iowa State University Press, Ames, Iowa). Other factors, such as a genetically similar donor parent, may also reduce the number of backcrosses necessary. As noted by Poehlman, backcrossing is easiest for simply inherited, dominant and easily recognized traits.

One process for adding or modifying a trait or locus in soybean variety XR28K10 comprises crossing XR28K10 plants grown from XR28K10 seed with plants of another soybean plant that comprises a desired trait lacking in XR28K10, selecting F1 progeny plants that possess the desired trait or locus to produce selected F1 progeny plants, crossing the selected progeny plants back to XR28K10 plants to produce backcross1 (BC1) progeny plants. The BC1F1 progeny plants that have the desired trait and the morphological characteristics of soybean variety XR28K10 are selected and backcrossed to XR28K10 to generate BC2F1 progeny plants. Additional backcrossing and selection of progeny plants with the desired trait will produce BC3F1, BC4F1, BC5F1, . . . BCxF1 generations of plants. The backcross populations of XR28K10 may be further characterized as having the physiological and morphological characteristics of soybean variety XR28K10 listed in Table 1 as determined at the 5% significance level when grown in the same environmental conditions and/or may be characterized by percent similarity or identity to XR28K10 as determined by SSR or other molecular markers. The above method may be utilized with fewer backcrosses in appropriate situations, such as when the donor parent is highly related or molecular markers are used in the selection step. Desired traits that may be used include those nucleic acids known in the art, some of which are listed herein, that will affect traits through nucleic acid expression or inhibition. Desired loci also include the introgression of FRT, Lox and/or other recombination sites for site specific integration. Desired loci further include QTLs, which may also affect a desired trait.

In addition, the above process and other similar processes described herein may be used to produce first generation progeny soybean seed by adding a step at the end of the process that comprises crossing XR28K10 with the introgressed trait or locus with a different soybean plant and harvesting the resultant first generation progeny soybean seed.

Transgenes and transformation methods provide means to engineer the genome of plants to contain and express foreign genetic elements, additional copies of endogenous elements, and/or modified versions of native or endogenous genetic elements in order to alter the traits of a plant in a specific manner that would be difficult or impossible to obtain with traditional plant breeding alone. Any heterologous DNA sequence(s), whether from a different species or from the same species, which are inserted into the genome using transformation, backcrossing or other methods known to one of skill in the art are referred to herein collectively as transgenes. The sequences are heterologous based on sequence source, location of integration, operably linked elements, or any combination thereof. Transgenic variants of soybean variety XR28K10, seeds, cells, and parts thereof or derived therefrom are provided.

In one example a process for modifying soybean variety XR28K10 with the addition of a desired trait, said process comprising transforming a soybean plant of variety XR28K10 with a transgene that confers a desired trait is provided. Therefore, transgenic XR28K10 soybean cells, plants, plant parts, and seeds produced from this process are provided. In some examples, the desired trait may be one or more of herbicide resistance, insect resistance, disease resistance, decreased phytate, modified fatty acid profile, modified fatty acid content, or carbohydrate metabolism. The specific gene may be any known in the art or listed herein, including but not limited to a polynucleotide conferring resistance to imidazolinone, sulfonylurea, glyphosate, glufosinate, triazine or benzonitrile herbicides; a polynucleotide encoding a Bacillus thuringiensis polypeptide, a polynucleotide encoding a phytase, a fatty acid desaturase (e.g., FAD-2, FAD-3), galactinol synthase, a raffinose synthetic enzyme; or a polynucleotide conferring resistance to soybean cyst nematode, brown stem rot, Phytophthora root rot, soybean mosaic virus, sudden death syndrome, or other plant pathogen.

Numerous methods for plant transformation have been developed, including biological and physical plant transformation protocols. See, for example, Miki et al., “Procedures for Introducing Foreign DNA into Plants” in Methods in Plant Molecular Biology and Biotechnology, Glick, B. R. and Thompson, J. E. Eds. (CRC Press, Inc., Boca Raton, 1993) pages 67-88; and Armstrong, “The First Decade of Maize Transformation: A Review and Future Perspective” (Maydica 44:101-109, 1999). In addition, expression vectors and in vitro culture methods for plant cell or tissue transformation and regeneration of plants are available. See, for example, Gruber et al., “Vectors for Plant Transformation” in Methods in Plant Molecular Biology and Biotechnology, Glick, B. R. and Thompson, J. E. Eds. (CRC Press, Inc., Boca Raton, 1993) pages 89-119.

The most prevalent types of plant transformation involve the construction of an expression vector. Such a vector comprises a DNA sequence that contains a gene under the control of or operatively linked to a regulatory element, for example a promoter. The vector may contain one or more genes and one or more regulatory elements.

A genetic trait which has been engineered into the genome of a particular soybean plant may then be moved into the genome of another variety using traditional breeding techniques that are well known in the plant breeding arts. For example, a backcrossing approach is commonly used to move a transgene from a transformed soybean variety into an elite soybean variety, and the resulting backcross conversion plant would then contain the transgene(s).

Various genetic elements can be introduced into the plant genome using transformation. These elements include, but are not limited to genes; coding sequences; inducible, constitutive, and tissue specific promoters; enhancing sequences; and signal and targeting sequences.

Transgenic plants can be used to produce commercial quantities of a foreign protein. Thus, techniques for the selection and propagation of transformed plants, which are well understood in the art, yield a plurality of transgenic plants that are harvested in a conventional manner, and a foreign protein then can be extracted from a tissue of interest or from total biomass. Protein extraction from plant biomass can be accomplished by known methods which are discussed, for example, by Heney and Orr, Anal. Biochem. 114:92-6 (1981).

A genetic map can be generated, primarily via conventional restriction fragment length polymorphisms (RFLP), polymerase chain reaction (PCR) analysis, simple sequence repeats (SSR) and single nucleotide polymorphisms (SNP) that identifies the approximate chromosomal location of the integrated DNA molecule. For exemplary methodologies in this regard, see Glick and Thompson, Methods in Plant Molecular Biology and Biotechnology, pp. 269-284 (CRC Press, Boca Raton, 1993).

Wang et al. discuss “Large Scale Identification, Mapping and Genotyping of Single-Nucleotide Polymorphisms in the Human Genome”, Science, 280:1077-1082, 1998, and similar capabilities are becoming increasingly available for the soybean genome. Map information concerning chromosomal location is useful for proprietary protection of a subject transgenic plant. If unauthorized propagation is undertaken and crosses made with other germplasm, the map of the integration region can be compared to similar maps for suspect plants to determine if the latter have a common parentage with the subject plant. Map comparisons could involve hybridizations, RFLP, PCR, SSR, sequencing or combinations thereof, all of which are conventional techniques. SNPs may also be used alone or in combination with other techniques.

Likewise, plants can be genetically engineered to express various phenotypes of agronomic interest. Through the transformation of soybean the expression of genes can be altered to enhance disease resistance, insect resistance, herbicide resistance, agronomic, grain quality and other traits. Transformation can also be used to insert DNA sequences which control or help control male-sterility. DNA sequences native to soybean as well as non-native DNA sequences can be transformed into soybean and used to alter levels of native or non-native proteins. Various promoters, targeting sequences, enhancing sequences, and other DNA sequences can be inserted into the genome for the purpose of altering the expression of proteins. Reduction of the activity of specific genes (also known as gene silencing, or gene suppression) is desirable for several aspects of genetic engineering in plants.

Many techniques for gene silencing are well known to one of skill in the art, including but not limited to knock-outs (such as by insertion of a transposable element such as mu (Vicki Chandler, The Maize Handbook ch. 118 (Springer-Verlag 1994) antisense technology (see, e.g., Sheehy et al. (1988) PNAS USA 85:8805-8809; and U.S. Pat. Nos. 5,107,065; 5,453,566; and 5,759,829); co-suppression (e.g., Taylor (1997) Plant Cell 9:1245; Jorgensen (1990) Trends Biotech. 8(12):340-344; Flavell (1994) PNAS USA 91:3490-3496; Finnegan et al. (1994) Bio/Technology 12:883-888; and Neuhuber et al. (1994) Mol. Gen. Genet. 244:230-241); RNA interference (Napoli et al. (1990) Plant Cell 2:279-289; U.S. Pat. No. 5,034,323; Sharp (1999) Genes Dev. 13:139-141; Zamore et al. (2000) Cell 101:25-33; and Montgomery et al. (1998) PNAS USA 95:15502-15507), virus-induced gene silencing (Burton, et al. (2000) Plant Cell 12:691-705; and Baulcombe (1999) Curr. Op. Plant Biol. 2:109-113); target-RNA-specific ribozymes (Haseloff et al. (1988) Nature 334: 585-591); hairpin structures (Smith et al. (2000) Nature 407:319-320; WO 99/53050; and WO 98/53083); microRNA (Aukerman & Sakai (2003) Plant Cell 15:2730-2741); ribozymes (Steinecke et al. (1992) EMBO J. 11:1525; and Perriman et al. (1993) Antisense Res. Dev. 3:253); oligonucleotide mediated targeted modification (e.g., WO 03/076574 and WO 99/25853); Zn-finger targeted molecules (e.g., WO 01/52620; WO 03/048345; and WO 00/42219); and other methods or combinations of the above methods known to those of skill in the art.

Exemplary nucleotide sequences that may be altered by genetic engineering include, but are not limited to, those categorized below.

1. Transgenes that Confer Resistance to Insects or Disease and that Encode:

(A) Plant disease resistance genes. Plant defenses are often activated by specific interaction between the product of a disease resistance gene (R) in the plant and the product of a corresponding avirulence (Avr) gene in the pathogen. A plant variety can be transformed with cloned resistance gene to engineer plants that are resistant to specific pathogen strains. See, for example Jones et al., Science 266: 789 (1994) (cloning of the tomato Cf-9 gene for resistance to Cladosporium fulvum); Martin et al., Science 262:1432 (1993) (tomato Pto gene for resistance to Pseudomonas syringae pv. tomato encodes a protein kinase); Mindrinos et al., Cell 78:1089 (1994) (Arabidopsis RPS2 gene for resistance to Pseudomonas syringae), McDowell & Woffenden, (2003) Trends Biotechnol. 21:178-83 and Toyoda et al., (2002) Transgenic Res. 11:567-82. A plant resistant to a disease is one that is more resistant to a pathogen as compared to the wild type plant.

(B) A Bacillus thuringiensis (Bt) protein, a derivative thereof or a synthetic polypeptide modeled thereon. See, for example, Geiser et al., Gene 48:109 (1986), who disclose the cloning and nucleotide sequence of a Bt delta-endotoxin gene. Moreover, DNA molecules encoding delta-endotoxin genes can be purchased from American Type Culture Collection (Rockville, Md.), for example, under ATCC Accession Nos. 40098, 67136, 31995 and 31998. Other non-limiting examples of Bacillus thuringiensis transgenes being genetically engineered are given in the following patents and patent applications and hereby are incorporated by reference for this purpose: U.S. Pat. Nos. 5,188,960; 5,689,052; 5,880,275; 5,986,177; 7,105,332; 7,208,474; WO 91/14778; WO 99/31248; WO 01/12731; WO 99/24581; WO 97/40162; US2002/0151709; US2003/0177528; US2005/0138685; US/0070245427; US2007/0245428; US2006/0241042; US2008/0020966; US2008/0020968; US2008/0020967; US2008/0172762; US2008/0172762; and US2009/0005306.

(C) An insect-specific hormone or pheromone such as an ecdysteroid or juvenile hormone, a variant thereof, a mimetic based thereon, or an antagonist or agonist thereof. See, for example, the disclosure by Hammock et al., Nature 344:458 (1990), of baculovirus expression of cloned juvenile hormone esterase, an inactivator of juvenile hormone.

(D) An insect-specific peptide which, upon expression, disrupts the physiology of the affected pest. For example, see the disclosures of Regan, J. Biol. Chem. 269:9 (1994) (expression cloning yields DNA coding for insect diuretic hormone receptor); Pratt et al., Biochem. Biophys. Res. Comm. 163:1243 (1989) (an allostatin is identified in Diploptera puntata); Chattopadhyay et al. (2004) Critical Reviews in Microbiology 30(1): 33-54 2004; Zjawiony (2004) J Nat Prod 67(2): 300-310; Carlini & Grossi-de-Sa (2002) Toxicon, 40(11): 1515-1539; Ussuf et al. (2001) Curr Sci. 80(7): 847-853; and Vasconcelos & Oliveira (2004) Toxicon 44(4):385-403. See also U.S. Pat. No. 5,266,317 to Tomalski et al., who disclose genes encoding insect-specific toxins.

(E) An enzyme responsible for a hyperaccumulation of a monoterpene, a sesquiterpene, a steroid, hydroxamic acid, a phenylpropanoid derivative or another non-protein molecule with insecticidal activity.

(F) An enzyme involved in the modification, including the post-translational modification, of a biologically active molecule; for example, a glycolytic enzyme, a proteolytic enzyme, a lipolytic enzyme, a nuclease, a cyclase, a transaminase, an esterase, a hydrolase, a phosphatase, a kinase, a phosphorylase, a polymerase, an elastase, a chitinase and a glucanase, whether natural or synthetic. See WO 93/02197, which discloses the nucleotide sequence of a callase gene. DNA molecules which contain chitinase-encoding sequences can be obtained, for example, from the ATCC under Accession Nos. 39637 and 67152. See also Kramer et al., Insect Biochem. Molec. Biol. 23:691 (1993), who teach the nucleotide sequence of a cDNA encoding tobacco hookworm chitinase, and Kawalleck et al., Plant Mol. Biol. 21:673 (1993), who provide the nucleotide sequence of the parsley ubi4-2 polyubiquitin gene, and U.S. Pat. Nos. 6,563,020; 7,145,060 and 7,087,810.

(G) A molecule that stimulates signal transduction. For example, see the disclosure by Botella et al., Plant Mol. Biol. 24:757 (1994), of nucleotide sequences for mung bean calmodulin cDNA clones, and Griess et al., Plant Physiol. 104:1467 (1994), who provide the nucleotide sequence of a maize calmodulin cDNA clone.

(H) A hydrophobic moment peptide. See WO 95/16776 and U.S. Pat. No. 5,580,852 disclosure of peptide derivatives of tachyplesin which inhibit fungal plant pathogens, and WO 95/18855 and U.S. Pat. No. 5,607,914 which teach synthetic antimicrobial peptides that confer disease resistance.

(I) A membrane permease, a channel former, or a channel blocker. For example, see the disclosure by Jaynes et al., Plant Sci. 89:43 (1993), of heterologous expression of a cecropin-beta lytic peptide analog to render transgenic tobacco plants resistant to Pseudomonas solanacearum.

(J) A viral-invasive protein or a complex toxin derived therefrom. For example, the accumulation of viral coat proteins in transformed plant cells imparts resistance to viral infection and/or disease development effected by the virus from which the coat protein gene is derived, as well as by related viruses. See Beachy et al., Ann. Rev. Phytopathol. 28:451 (1990). Coat protein-mediated resistance has been conferred upon transformed plants against alfalfa mosaic virus, cucumber mosaic virus, tobacco streak virus, potato virus X, potato virus Y, tobacco etch virus, tobacco rattle virus and tobacco mosaic virus.

(K) An insect-specific antibody or an immunotoxin derived therefrom. Thus, an antibody targeted to a critical metabolic function in the insect gut would inactivate an affected enzyme, killing the insect. Cf. Taylor et al., Abstract #497, Seventh Int'l Symposium on Molecular Plant-Microbe Interactions (Edinburgh, Scotland, 1994) (enzymatic inactivation in transgenic tobacco via production of single-chain antibody fragments).

(L) A virus-specific antibody. See, for example, Tavladoraki et al., Nature 366:469 (1993), who show that transgenic plants expressing recombinant antibody genes are protected from virus attack.

(M) A developmental-arrestive protein produced in nature by a pathogen or a parasite. Thus, fungal endo alpha-1,4-D-polygalacturonases facilitate fungal colonization and plant nutrient release by solubilizing plant cell wall homo-alpha-1,4-D-galacturonase. See Lamb et al., Bio/Technology 10:1436 (1992). The cloning and characterization of a gene which encodes a bean endopolygalacturonase-inhibiting protein is described by Toubart et al., Plant J. 2:367 (1992).

(N) A developmental-arrestive protein produced in nature by a plant. For example, Logemann et al., Bio/Technology 10:305 (1992), have shown that transgenic plants expressing the barley ribosome-inactivating gene have an increased resistance to fungal disease.

(O) Genes involved in the systemic acquired resistance (SAR) Response and/or the pathogenesis related genes. Briggs Current Biology, 5:128-131 (1995), Pieterse & Van Loon (2004) Curr. Opin. Plant Bio. 7:456-64; and Somssich (2003) Cell 113:815-6.

(P) Antifungal genes (Cornelissen and Melchers, Plant Physiol. 101:709-712, (1993); Parijs et al., Planta 183:258-264, (1991); Bushnell et al., Can. J. Plant Path. 20:137-149 (1998). Also see US2002/0166141; US2007/0274972; US2007/0192899; US20080022426; and U.S. Pat. Nos. 6,891,085; 7,306,946; and 7,598,346.

(Q) Detoxification genes, such as for fumonisin, beauvericin, moniliformin and zearalenone and their structurally related derivatives. For example, see U.S. Pat. Nos. 5,716,820; 5,792,931; 5,798,255; 5,846,812; 6,083,736; 6,538,177; 6,388,171 and 6,812,380.

(R) Cystatin and cysteine proteinase inhibitors. See U.S. Pat. No. 7,205,453.

(S) Defensin genes. See WO 03/000863 and U.S. Pat. Nos. 6,911,577; 6,855,865; 6,777,592 and 7,238,781.

(T) Genes conferring resistance to nematodes. See e.g. WO 96/30517; WO 93/19181, WO 03/033651; and Urwin et al., Planta 204:472-479 (1998); Williamson (1999) Curr Opin Plant Bio. 2:327-31; and U.S. Pat. Nos. 6,284,948 and 7,301,069.

(U) Genes that confer resistance to Phytophthora Root Rot, such as the Rps 1, Rps 1-a, Rps 1-b, Rps 1-c, Rps 1-d, Rps 1-e, Rps 1-k, Rps 2, Rps 3-a, Rps 3-b, Rps 3-c, Rps 4, Rps 5, Rps 6, Rps 7 and other Rps genes. See, for example, Shoemaker et al, Phytophthora Root Rot Resistance Gene Mapping in Soybean, Plant Genome IV Conference, San Diego, Calif. (1995).

(V) Genes that confer resistance to Brown Stem Rot, such as described in U.S. Pat. No. 5,689,035 and incorporated by reference for this purpose.

2. Transgenes that Confer Resistance to a Herbicide, for Example:

(A) A herbicide that inhibits the growing point or meristem, such as an imidazolinone or a sulfonylurea. Exemplary genes in this category code for mutant ALS and AHAS enzyme as described, for example, by Lee et al., EMBO J. 7:1241 (1988); and Miki et al., Theor. Appl. Genet. 80:449 (1990), respectively. See also, U.S. Pat. Nos. 5,605,011; 5,013,659; 5,141,870; 5,767,361; 5,731,180; 5,304,732; 4,761,373; 5,331,107; 5,928,937; and 5,378,824; US2007/0214515; and WO 96/33270.

(B) Glyphosate (resistance imparted by mutant 5-enolpyruvl-3-phosphikimate synthase (EPSP) and aroA genes, respectively) and other phosphono compounds such as glufosinate (phosphinothricin acetyl transferase (PAT) and Streptomyces hygroscopicus phosphinothricin acetyl transferase (bar) genes), and pyridinoxy or phenoxy proprionic acids and cyclohexones (ACCase inhibitor-encoding genes). See, for example, U.S. Pat. No. 4,940,835 to Shah et al., which discloses the nucleotide sequence of a form of EPSPS which can confer glyphosate resistance. U.S. Pat. No. 5,627,061 to Barry et al. also describes genes encoding EPSPS enzymes. See also U.S. Pat. Nos. 6,566,587; 6,338,961; 6,248,876; 6,040,497; 5,804,425; 5,633,435; 5,145,783; 4,971,908; 5,312,910; 5,188,642; 4,940,835; 5,866,775; 6,225,114; 6,130,366; 5,310,667; 4,535,060; 4,769,061; 5,633,448; 5,510,471; Re. 36,449; RE 37,287 E; and 5,491,288; and international publications EP1173580; WO 01/66704; EP1173581 and EP1173582, which are incorporated herein by reference for this purpose. Glyphosate resistance is also imparted to plants that express a gene that encodes a glyphosate oxido-reductase enzyme as described more fully in U.S. Pat. Nos. 5,776,760 and 5,463,175, which are incorporated herein by reference for this purpose. In addition glyphosate resistance can be imparted to plants by the over expression of genes encoding glyphosate N-acetyltransferase. See, for example, U.S. Application Serial Nos. US2004/0082770; US2005/0246798; and US2008/0234130. A DNA molecule encoding a mutant aroA gene can be obtained under ATCC accession No. 39256, and the nucleotide sequence of the mutant gene is disclosed in U.S. Pat. No. 4,769,061 to Comai. European Patent Application No. 0 333 033 to Kumada et al. and U.S. Pat. No. 4,975,374 to Goodman et al. disclose nucleotide sequences of glutamine synthetase genes which confer resistance to herbicides such as L-phosphinothricin. The nucleotide sequence of a phosphinothricin-acetyl-transferase gene is provided in European Patent No. 0 242 246 and 0 242 236 to Leemans et al. De Greef et al., Bio/Technology 7:61 (1989), describe the production of transgenic plants that express chimeric bar genes coding for phosphinothricin acetyl transferase activity. See also, U.S. Pat. Nos. 5,969,213; 5,489,520; 5,550,318; 5,874,265; 5,919,675; 5,561,236; 5,648,477; 5,646,024; 6,177,616; and 5,879,903, which are incorporated herein by reference for this purpose. Exemplary genes conferring resistance to phenoxy proprionic acids and cyclohexones, such as sethoxydim and haloxyfop, are the Acc1-S1, Acc1-S2 and Acc1-S3 genes described by Marshall et al., Theor. Appl. Genet. 83:435 (1992).

(C) A herbicide that inhibits photosynthesis, such as a triazine (psbA and gs+ genes) and a benzonitrile (nitrilase gene). Przibilla et al., Plant Cell 3:169 (1991), describe the transformation of Chlamydomonas with plasmids encoding mutant psbA genes. Nucleotide sequences for nitrilase genes are disclosed in U.S. Pat. No. 4,810,648 to Stalker, and DNA molecules containing these genes are available under ATCC Accession Nos. 53435, 67441 and 67442. Cloning and expression of DNA coding for a glutathione S-transferase is described by Hayes et al., Biochem. J. 285:173 (1992).

(D) Acetohydroxy acid synthase, which has been found to make plants that express this enzyme resistant to multiple types of herbicides, has been introduced into a variety of plants (see, e.g., Hattori et al. (1995) Mol Gen Genet 246:419). Other genes that confer resistance to herbicides include: a gene encoding a chimeric protein of rat cytochrome P4507A1 and yeast NADPH-cytochrome P450 oxidoreductase (Shiota et al. (1994) Plant Physiol 106:17), genes for glutathione reductase and superoxide dismutase (Aono et al. (1995) Plant Cell Physiol 36:1687, and genes for various phosphotransferases (Datta et al. (1992) Plant Mol Biol 20:619).

(E) Protoporphyrinogen oxidase (protox) is necessary for the production of chlorophyll, which is necessary for all plant survival. The protox enzyme serves as the target for a variety of herbicidal compounds. These herbicides also inhibit growth of all the different species of plants present, causing their total destruction. The development of plants containing altered protox activity which are resistant to these herbicides are described in U.S. Pat. Nos. 6,288,306; 6,282,837; and 5,767,373; and WO 01/12825.

3. Transgenes that Confer or Contribute to an Altered Grain Characteristic, such as:

(A) Altered fatty acids, for example, by

-   -   (1) Down-regulation of stearoyl-ACP desaturase to increase         stearic acid content of the plant. See Knultzon et al., Proc.         Natl. Acad. Sci. USA 89:2624 (1992) and WO 99/64579 (Genes for         Desaturases to Alter Lipid Profiles in Corn),     -   (2) Elevating oleic acid via FAD-2 gene modification and/or         decreasing linolenic acid via FAD-3 gene modification (see U.S.         Pat. Nos. 6,063,947; 6,323,392; 6,372,965; and WO 93/11245),     -   (3) Altering conjugated linolenic or linoleic acid content, such         as in WO 01/12800,     -   (4) Altering LEC1, AGP, Dek1, Superal1, mi1 ps, various Ipa         genes such as Ipa1, Ipa3, hpt or hggt. For example, see WO         02/42424; WO 98/22604; WO 03/011015; U.S. Pat. No. 6,423,886;         U.S. Pat. No. 6,197,561; U.S. Pat. No. 6,825,397;         US2003/0079247; US2003/0204870; WO 02/057439; WO 03/011015; and         Rivera-Madrid, R. et al. Proc. Natl. Acad. Sci. 92:5620-5624         (1995).

B) Altered phosphorus content, for example, by the

-   -   (1) Introduction of a phytase-encoding gene would enhance         breakdown of phytate, adding more free phosphate to the         transformed plant. For example, see Van Hartingsveldt et al.,         Gene 127:87 (1993), for a disclosure of the nucleotide sequence         of an Aspergillus niger phytase gene.     -   (2) Modulating a gene that reduces phytate content. In maize,         this, for example, could be accomplished, by cloning and then         re-introducing DNA associated with one or more of the alleles,         such as the LPA alleles, identified in maize mutants         characterized by low levels of phytic acid, such as in WO         05/113778 and/or by altering inositol kinase activity as in WO         02/059324, U.S. Pat. No. 7,067,720, WO 03/027243,         US2003/0079247, WO 99/05298, U.S. Pat. No. 6,197,561, U.S. Pat.         No. 6,291,224, U.S. Pat. No. 6,391,348, WO 98/45448, WO         99/55882, WO 01/04147.

(C) Altered carbohydrates, for example, by altering a gene for an enzyme that affects the branching pattern of starch or, a gene altering thioredoxin such as NTR and/or TRX (see U.S. Pat. No. 6,531,648 which is incorporated by reference for this purpose) and/or a gamma zein knock out or mutant such as cs27 or TUSC27 or en27 (See U.S. Pat. No. 6,858,778; US2005/0160488; and US2005/0204418; which are incorporated by reference for this purpose). See Shiroza et al., J. Bacteriol. 170:810 (1988) (nucleotide sequence of Streptococcus mutans fructosyltransferase gene), Steinmetz et al., Mol. Gen. Genet. 200:220 (1985) (nucleotide sequence of Bacillus subtilis levansucrase gene), Pen et al., Bio/Technology 10:292 (1992) (production of transgenic plants that express Bacillus licheniformis alpha-amylase), Elliot et al., Plant Mol. Biol. 21:515 (1993) (nucleotide sequences of tomato invertase genes), Søgaard et al., J. Biol. Chem. 268:22480 (1993) (site-directed mutagenesis of barley alpha-amylase gene), and Fisher et al., Plant Physiol. 102:1045 (1993) (maize endosperm starch branching enzyme II), WO 99/10498 (improved digestibility and/or starch extraction through modification of UDP-D-xylose 4-epimerase, Fragile 1 and 2, Ref1 HCHL, C4H), U.S. Pat. No. 6,232,529 (method of producing high oil seed by modification of starch levels (AGP)). The fatty acid modification genes mentioned herein may also be used to affect starch content and/or composition through the interrelationship of the starch and oil pathways.

(D) Altered antioxidant content or composition, such as alteration of tocopherol or tocotrienols. For example, see U.S. Pat. No. 6,787,683; U.S. Pat. No. 7,154,029; and WO 00/68393 involving the manipulation of antioxidant levels, and WO 03/082899 through alteration of a homogentisate geranyl geranyl transferase (hggt).

(E) Altered essential seed amino acids. For example, see U.S. Pat. No. 6,127,600 (method of increasing accumulation of essential amino acids in seeds), U.S. Pat. No. 6,080,913 (binary methods of increasing accumulation of essential amino acids in seeds), U.S. Pat. No. 5,990,389 (high lysine), WO 99/40209 (alteration of amino acid compositions in seeds), WO 99/29882 (methods for altering amino acid content of proteins), U.S. Pat. No. 5,850,016 (alteration of amino acid compositions in seeds), WO 98/20133 (proteins with enhanced levels of essential amino acids), U.S. Pat. No. 5,885,802 (high methionine), U.S. Pat. No. 5,885,801 (high threonine), U.S. Pat. No. 6,664,445 (plant amino acid biosynthetic enzymes), U.S. Pat. No. 6,459,019 (increased lysine and threonine), U.S. Pat. No. 6,441,274 (plant tryptophan synthase beta subunit), U.S. Pat. No. 6,346,403 (methionine metabolic enzymes), U.S. Pat. No. 5,939,599 (high sulfur), U.S. Pat. No. 5,912,414 (increased methionine), WO 98/56935 (plant amino acid biosynthetic enzymes), WO 98/45458 (engineered seed protein having higher percentage of essential amino acids), WO 98/42831 (increased lysine), U.S. Pat. No. 5,633,436 (increasing sulfur amino acid content), U.S. Pat. No. 5,559,223 (synthetic storage proteins with defined structure containing programmable levels of essential amino acids for improvement of the nutritional value of plants), WO 96/01905 (increased threonine), WO 95/15392 (increased lysine), U.S. Pat. No. 6,930,225, U.S. Pat. No. 7,179,955, US2004/0068767, U.S. Pat. No. 6,803,498, WO 01/79516.

4. Genes that Control Male-Sterility

There are several methods of conferring genetic male sterility available, such as multiple mutant genes at separate locations within the genome that confer male sterility, as disclosed in U.S. Pat. Nos. 4,654,465 and 4,727,219 to Brar et al. and chromosomal translocations as described by Patterson in U.S. Pat. Nos. 3,861,709 and 3,710,511. In addition to these methods, Albertsen et al., U.S. Pat. No. 5,432,068, describe a system of nuclear male sterility which includes: identifying a gene which is critical to male fertility; silencing this native gene which is critical to male fertility; removing the native promoter from the essential male fertility gene and replacing it with an inducible promoter; inserting this genetically engineered gene back into the plant; and thus creating a plant that is male sterile because the inducible promoter is not “on” resulting in the male fertility gene not being transcribed. Fertility is restored by inducing, or turning “on”, the promoter, which in turn allows the gene that confers male fertility to be transcribed. Male sterile soybean lines and characterization are discussed in Palmer (2000) Crop Sci 40:78-83, and Jin et al. (1997) Sex Plant Reprod 10:13-21.

(A) Introduction of a deacetylase gene under the control of a tapetum-specific promoter and with the application of the chemical N—Ac-PPT (WO 01/29237).

(B) Introduction of various stamen-specific promoters (WO 92/13956, WO 92/13957).

(C) Introduction of the barnase and the barstar gene (Paul et al. Plant Mol. Biol. 19:611-622, 1992).

For additional examples of nuclear male and female sterility systems and genes, see also, U.S. Pat. Nos. 5,859,341; 6,297,426; 5,478,369; 5,824,524; 5,850,014; and 6,265,640; all of which are hereby incorporated by reference.

5. Polynucleotides that create a site for site specific DNA integration. This includes the introduction of at least one FRT site that may be used in the FLP/FRT system and/or a Lox site that may be used in the Cre/Lox system. For example, see Lyznik et al., Site-Specific Recombination for Genetic Engineering in Plants, Plant Cell Rep (2003) 21:925-932 and WO 99/25821, which are hereby incorporated by reference. Other systems that may be used include the Gin recombinase of phage Mu (Maeser et al. (1991) Mol Gen Genet 230:170-176); the Pin recombinase of E. coli (Enomoto et al. (1983) J Bacteriol 156:663-668); and the R/RS system of the pSRi plasmid (Araki et al. (1992) J Mol Biol 182:191-203). 6. Genes that affect abiotic stress resistance (including but not limited to flowering, ear and seed development, enhancement of nitrogen utilization efficiency, altered nitrogen responsiveness, drought resistance or tolerance, cold resistance or tolerance, and salt resistance or tolerance) and increased yield under stress. For example, see: WO 00/73475 where water use efficiency is altered through alteration of malate; U.S. Pat. Nos. 5,892,009, 5,965,705, 5,929,305, 5,891,859, 6,417,428, 6,664,446, 6,706,866, 6,717,034, 6,801,104, WO 00/060089, WO 01/026459, WO 00/1035725, WO 01/034726, WO 01/035727, WO 00/1036444, WO 01/036597, WO 01/036598, WO 00/2015675, WO 02/017430, WO 02/077185, WO 02/079403, WO 03/013227, WO 03/013228, WO 03/014327, WO 04/031349, WO 04/076638, WO 98/09521, and WO 99/38977 describing genes, including CBF genes and transcription factors effective in mitigating the negative effects of freezing, high salinity, and drought on plants, as well as conferring other positive effects on plant phenotype; US2004/0148654 and WO 01/36596 where abscisic acid is altered in plants resulting in improved plant phenotype such as increased yield and/or increased tolerance to abiotic stress; WO 00/006341, WO 04/090143, U.S. Pat. No. 7,531,723 and U.S. Pat. No. 6,992,237 where cytokinin expression is modified resulting in plants with increased stress tolerance, such as drought tolerance, and/or increased yield. Also see WO 02/02776, WO 03/052063, JP2002281975, U.S. Pat. No. 6,084,153, WO 01/64898, U.S. Pat. No. 6,177,275, and U.S. Pat. No. 6,107,547 (enhancement of nitrogen utilization and altered nitrogen responsiveness). For ethylene alteration, see US2004/0128719, US2003/0166197, and WO 00/32761. For plant transcription factors or transcriptional regulators of abiotic stress, see e.g. US2004/0098764 or US2004/0078852.

Other genes and transcription factors that affect plant growth and agronomic traits such as yield, flowering, plant growth and/or plant structure, can be introduced or introgressed into plants, see e.g., WO 97/49811 (LHY), WO 98/56918 (ESD4), WO 97/10339 and U.S. Pat. No. 6,573,430 (TFL), U.S. Pat. No. 6,713,663 (FT), WO 96/14414 (CON), WO 96/38560, WO 01/21822 (VRN1), WO 00/44918 (VRN2), WO 99/49064 (GI), WO 00/46358 (FRI), WO 97/29123, U.S. Pat. No. 6,794,560, U.S. Pat. No. 6,307,126 (GAI), WO 99/09174 (D8 and Rht), and WO 04/076638 and WO 04/031349 (transcription factors).

Development of Soybean Sublines

Sublines of XR28K10 may also be developed. Although XR28K10 contains substantially fixed genetics and is phenotypically uniform with no off-types expected, there still remains a small proportion of segregating loci either within individuals or within the population as a whole. Sublining provides the ability to select for these loci, which have no apparent morphological or phenotypic effect on the plant characteristics, but may have an affect on overall yield. For example, the methods described in U.S. Pat. No. 5,437,697 and US2005/0071901 may be utilized by a breeder of ordinary skill in the art to identify genetic loci that are associated with yield potential to further purify the variety in order to increase its yield (both of which are herein incorporated by reference). Based on these teachings, a breeder of ordinary skill in the art may fix agronomically important loci by making them homozygous in order to optimize the performance of the variety. No crosses to a different variety are made, and so a new genetic variety is not created and the overall genetic composition of the variety remains essentially the same. The development of soybean sublines and the use of accelerated yield technology is a plant breeding technique.

Soybean varieties such as XR28K10 are typically developed for use in seed and grain production. However, soybean varieties such as XR28K10 also provide a source of breeding material that may be used to develop new soybean varieties. Plant breeding techniques known in the art and used in a soybean plant breeding program include, but are not limited to, recurrent selection, mass selection, bulk selection, backcrossing, pedigree breeding, open pollination breeding, restriction fragment length polymorphism enhanced selection, genetic marker enhanced selection, making double haploids, and transformation. Often combinations of these techniques are used. The development of soybean varieties in a plant breeding program requires, in general, the development and evaluation of homozygous varieties. There are many analytical methods available to evaluate a new variety. The oldest and most traditional method of analysis is the observation of phenotypic traits but genotypic analysis may also be used.

Methods for producing a soybean plant by crossing a first parent soybean plant with a second parent soybean plant wherein the first and/or second parent soybean plant is variety XR28K10 are provided. The other parent may be any soybean plant, such as a soybean plant that is part of a synthetic or natural population. Any such methods using soybean variety XR28K10 include but are not limited to:selfing, sibbing, backcrossing, mass selection, pedigree breeding, bulk selection, hybrid production, crossing to populations, and the like. These methods are well known in the art and some of the more commonly used breeding methods are described below. Descriptions of breeding methods can be found in one of several reference books (e.g., Allard, Principles of Plant Breeding, 1960; Simmonds, Principles of Crop Improvement, 1979; Sneep et al., 1979; Fehr, “Breeding Methods for Cultivar Development”, Chapter 7, Soybean Improvement, Production and Uses, 2^(nd) ed., Wilcox editor, 1987).

Pedigree breeding starts with the crossing of two genotypes, such as XR28K10 and another soybean variety having one or more desirable characteristics that is lacking or which complements XR28K10. If the two original parents do not provide all the desired characteristics, other sources can be included in the breeding population. In the pedigree method, superior plants are selfed and selected in successive filial generations. In the succeeding filial generations, the heterozygous allele condition gives way to the homozygous allele condition as a result of inbreeding. Typically in the pedigree method of breeding, five or more successive filial generations of selfing and selection is practiced: F1→F2; F2→F3; F3→F4; F4→F5, etc. After a sufficient amount of inbreeding, successive filial generations will serve to increase seed of the developed variety. Typically, the developed variety comprises homozygous alleles at about 95% or more of its loci.

In addition to being used to create backcross conversion populations, backcrossing can also be used in combination with pedigree breeding. As discussed previously, backcrossing can be used to transfer one or more specifically desirable traits from one variety (the donor parent) to a developed variety (the recurrent parent), which has overall good agronomic characteristics yet lacks that desirable trait or traits. However, the same procedure can be used to move the progeny toward the genotype of the recurrent parent but at the same time retain many components of the non-recurrent parent by stopping the backcrossing at an early stage and proceeding with selfing and selection. For example, a soybean variety may be crossed with another variety to produce a first generation progeny plant. The first generation progeny plant may then be backcrossed to one of its parent varieties to create a BC1F1. Progeny are selfed and selected so that the newly developed variety has many of the attributes of the recurrent parent and yet several of the desired attributes of the donor parent. This approach leverages the value and strengths of the recurrent parent for use in new soybean varieties.

Therefore, in some examples a method of making a backcross conversion of soybean variety XR28K10, comprising the steps of crossing a plant of soybean variety XR28K10 with a donor plant possessing a desired trait, selecting an F1 progeny plant containing the desired trait, and backcrossing the selected F1 progeny plant to a plant of soybean variety XR28K10 are provided. This method may further comprise the step of obtaining a molecular marker profile of soybean variety XR28K10 and using the molecular marker profile to select for a progeny plant with the desired trait and the molecular marker profile of XR28K10. In one example the desired trait is a mutant gene or transgene present in the donor parent.

Recurrent selection is a method used in a plant breeding program to improve a population of plants. XR28K10 is suitable for use in a recurrent selection program. The method entails individual plants cross pollinating with each other to form progeny. The progeny are grown and the superior progeny selected by any number of selection methods, which include individual plant, half-sib progeny, full-sib progeny and selfed progeny. The selected progeny are cross pollinated with each other to form progeny for another population. This population is planted and again superior plants are selected to cross pollinate with each other. Recurrent selection is a cyclical process and therefore can be repeated as many times as desired. The objective of recurrent selection is to improve the traits of a population. The improved population can then be used as a source of breeding material to obtain new varieties for commercial or breeding use, including the production of a synthetic cultivar. A synthetic cultivar is the resultant progeny formed by the intercrossing of several selected varieties.

Mass selection is a useful technique when used in conjunction with molecular marker enhanced selection. In mass selection seeds from individuals are selected based on phenotype or genotype. These selected seeds are then bulked and used to grow the next generation. Bulk selection requires growing a population of plants in a bulk plot, allowing the plants to self-pollinate, harvesting the seed in bulk and then using a sample of the seed harvested in bulk to plant the next generation. Also, instead of self pollination, directed pollination could be used as part of the breeding program.

Mutation breeding is another method of introducing new traits into soybean variety XR28K10. Mutations that occur spontaneously or are artificially induced can be useful sources of variability for a plant breeder. The goal of artificial mutagenesis is to increase the rate of mutation for a desired characteristic. Mutation rates can be increased by many different means including temperature, long-term seed storage, tissue culture conditions, radiation; such as X-rays, Gamma rays (e.g., cobalt 60 or cesium 137), neutrons, (product of nuclear fission by uranium 235 in an atomic reactor), beta radiation (emitted from radioisotopes such as phosphorus 32 or carbon 14), ultraviolet radiation (preferably from 2500 to 2900 nm), or chemical mutagens such as base analogues (5-bromo-uracil), related compounds (8-ethoxy caffeine), antibiotics (streptonigrin), alkylating agents (sulfur mustards, nitrogen mustards, epoxides, ethylenamines, sulfates, sulfonates, sulfones, lactones), azide, hydroxylamine, nitrous acid, or acridines. Once a desired trait is observed through mutagenesis, the trait may then be incorporated into existing germplasm by traditional breeding techniques. Details of mutation breeding can be found in “Principles of Cultivar Development” Fehr, 1993 Macmillan Publishing Company. In addition, mutations created in other soybean plants may be used to produce a backcross conversion of XR28K10 that comprises such mutation.

Molecular markers, which includes markers identified through the use of techniques such as isozyme electrophoresis, restriction fragment length polymorphisms (RFLPs), randomly amplified polymorphic DNAs (RAPDs), arbitrarily primed polymerase chain reaction (AP-PCR), DNA amplification fingerprinting (DAF), sequence characterized amplified regions (SCARs), amplified fragment length polymorphisms (AFLPs), simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs), may be used in plant breeding methods utilizing XR28K10.

Isozyme electrophoresis and RFLPs have been widely used to determine genetic composition. Shoemaker and Olsen, ((1993) Molecular Linkage Map of Soybean (Glycine max L. Merr.). p. 6.131-6.138. In S. J. O'Brien (ed.) Genetic Maps: Locus Maps of Complex Genomes. Cold Spring Harbor Laboratory Press. Cold Spring Harbor, N.Y.), developed a molecular genetic linkage map that consisted of 25 linkage groups with about 365 RFLP, 11 RAPD (random amplified polymorphic DNA), three classical markers, and four isozyme loci. See also, Shoemaker R. C. 1994 RFLP Map of Soybean. P. 299-309 In R. L. Phillips and I. K. Vasil (ed.) DNA-based markers in plants. Kluwer Academic Press Dordrecht, the Netherlands.

SSR technology is an efficient and practical marker technology; more marker loci can be routinely used and more alleles per marker locus can be found using SSRs in comparison to RFLPs. For example Diwan and Cregan, described a highly polymorphic microsatellite loci in soybean with as many as 26 alleles. (Diwan, N., and P. B. Cregan 1997 Automated sizing of fluorescent-labeled simple sequence repeat (SSR) markers to assay genetic variation in Soybean Theor. Appl. Genet. 95:220-225). Single nucleotide polymorphisms (SNPs) may also be used to identify the unique genetic composition of the XR28K10 and progeny varieties retaining or derived from that unique genetic composition. Various molecular marker techniques may be used in combination to enhance overall resolution.

Soybean DNA molecular marker linkage maps have been rapidly constructed and widely implemented in genetic studies. One such study is described in Cregan et. al, “An Integrated Genetic Linkage Map of the Soybean Genome” Crop Science 39:1464-1490 (1999). Sequences and PCR conditions of SSR Loci in Soybean as well as the most current genetic map may be found in Soybase on the world wide web.

One use of molecular markers is quantitative trait loci (QTL) mapping. QTL mapping is the use of markers, which are known to be closely linked to alleles that have measurable effects on a quantitative trait. Selection in the breeding process is based upon the accumulation of markers linked to the positive effecting alleles and/or the elimination of the markers linked to the negative effecting alleles from the plant genome.

Molecular markers can also be used during the breeding process for the selection of qualitative traits. For example, markers closely linked to alleles or markers containing sequences within the actual alleles of interest can be used to select plants that contain the alleles of interest during a backcrossing breeding program. The markers can also be used to select for the genome of the recurrent parent and against the genome of the donor parent. Using this procedure can minimize the amount of genome from the donor parent that remains in the selected plants. It can also be used to reduce the number of crosses back to the recurrent parent needed in a backcrossing program. The use of molecular markers in the selection process is often called genetic marker enhanced selection.

Production of Double Haploids

The production of double haploids can also be used for the development of plants with a homozygous phenotype in the breeding program. For example, a soybean plant for which XR28K10 is a parent can be used to produce double haploid plants. Double haploids are produced by the doubling of a set of chromosomes (1N) from a heterozygous plant to produce a completely homozygous individual. For example, see Wan et al., “Efficient Production of Doubled Haploid Plants Through Colchicine Treatment of Anther-Derived Maize Callus”, Theoretical and Applied Genetics, 77:889-892, 1989 and US2003/0005479. This can be advantageous because the process omits the generations of selfing needed to obtain a homozygous plant from a heterozygous source.

Methods for obtaining haploid plants are disclosed in Kobayashi, M. et al., J Heredity 71:9-14, 1980, Pollacsek, M., Agronomie (Paris) 12:247-251, 1992; Cho-Un-Haing et al., J Plant Biol., 1996, 39:185-188; Verdoodt, L., et al., 1998, 96:294-300; Genetic Manipulation in Plant Breeding, Proceedings International Symposium Organized by EUCARPIA, Sep. 8-13, 1985, Berlin, Germany; Chalyk et al., 1994, Maize Genet Coop. Newsletter 68:47. Double haploid technology in soybean is discussed in Croser et al. (2006) Crit Rev Plant Sci 25:139-157; and Rodrigues et al. (2006) Brazilian Arc Biol Tech 49:537-545.

In some examples a process for making a substantially homozygous XR28K10 progeny plant by producing or obtaining a seed from the cross of XR28K10 and another soybean plant and applying double haploid methods to the F1 seed or F1 plant or to any successive filial generation is provided. Based on studies in maize and currently being conducted in soybean, such methods would decrease the number of generations required to produce a variety with similar genetics or characteristics to XR28K10. See Bernardo, R. and Kahler, A. L., Theor. Appl. Genet. 102:986-992, 2001.

In particular, a process of making seed retaining the molecular marker profile of soybean variety XR28K10 is contemplated, such process comprising obtaining or producing F1 seed for which soybean variety XR28K10 is a parent, inducing doubled haploids to create progeny without the occurrence of meiotic segregation, obtaining the molecular marker profile of soybean variety XR28K10, and selecting progeny that retain the molecular marker profile of XR28K10.

Methods using seeds, plants, cells, or plant parts of variety XR28K10 in tissue culture are provided, as are the cultures, plants, parts, cells, and/or seeds derived therefrom. Tissue culture of various tissues of soybeans and regeneration of plants therefrom is well known and widely published. For example, see Komatsuda, T. et al., “Genotype X Sucrose Interactions for Somatic Embryogenesis in Soybean,” Crop Sci. 31:333-337 (1991); Stephens, P. A. et al., “Agronomic Evaluation of Tissue-Culture-Derived Soybean Plants,” Theor. Appl. Genet. (1991) 82:633-635; Komatsuda, T. et al., “Maturation and Germination of Somatic Embryos as Affected by Sucrose and Plant Growth Regulators in Soybeans Glycine gracilis Skvortz and Glycine max (L.) Merr.,” Plant Cell, Tissue and Organ Culture, 28:103-113 (1992); Dhir, S. et al., “Regeneration of Fertile Plants from Protoplasts of Soybean (Glycine max L. Merr.): Genotypic Differences in Culture Response,” Plant Cell Reports (1992) 11:285-289; Pandey, P. et al., “Plant Regeneration from Leaf and Hypocotyl Explants of Glycine wightii (W. and A.) VERDC. var. longicauda,” Japan J. Breed. 42:1-5 (1992); and Shetty, K., et al., “Stimulation of In Vitro Shoot Organogenesis in Glycine max (Merrill.) by Allantoin and Amides,” Plant Science 81:(1992) 245-251; as well as U.S. Pat. No. 5,024,944, issued Jun. 18, 1991 to Collins et al. and U.S. Pat. No. 5,008,200, issued Apr. 16, 1991 to Ranch et al., the disclosures of which are hereby incorporated herein in their entirety by reference. Thus, another aspect is to provide cells which upon growth and differentiation produce soybean plants having the physiological and morphological characteristics of soybean variety XR28K10.

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Applicant made a deposit of seeds of Soybean Variety XR28K10 with the American Type Culture Collection (ATCC), Manassas, Va. 20110 USA, ATCC Deposit No. PTA-13150. The seeds deposited with the ATCC on Aug. 13, 2012 were taken from the seed stock maintained by Pioneer Hi-Bred International, Inc., 7250 NW 62^(nd) Avenue, Johnston, Iowa 50131 since prior to the filing date of this application. Access to this seed stock will be available during the pendency of the application to the Commissioner of Patents and Trademarks and persons determined by the Commissioner to be entitled thereto upon request. Upon allowance of any claims in the application, the Applicant will make the deposit available to the public pursuant to 37 C.F.R. §1.808. This deposit of Soybean Variety XR28K10 will be maintained in the ATCC depository, which is a public depository, for a period of 30 years, or 5 years after the most recent request, or for the enforceable life of the patent, whichever is longer, and will be replaced if it becomes nonviable during that period. Additionally, Applicant has or will satisfy all the requirements of 37 C.F.R. §§1.801-1.809, including providing an indication of the viability of the sample upon deposit. Applicant has no authority to waive any restrictions imposed by law on the transfer of biological material or its transportation in commerce. Applicant does not waive any infringement of their rights granted under this patent or under the Plant Variety Protection Act (7 USC 2321 et seq.).

TABLE 1 Variety Description Information for XR28K10 Current Variety Name XR28K10 Relative Maturity 28 Herbicide Resistance RR Harvest Standability Field Emergence Hypocotyl Length Phytophthora Gene 1K Phytophthora Race 5 Phytophthora Race 7 Phytophthora Race 25 Phytophthora Field Tolerance Brown Stem Rot Iron Chlorosis White Mold Tolerance Sudden Death Syndrome Cyst Nematode Race 1 Cyst Nematode Race 2 Cyst Nematode Race 3 Cyst Nematode Race 5 Cyst Nematode Race 14 Aphid Antibiosis Root-knot Nematode— Southern Root-knot Nematode— Peanut Stem Canker Genetic Stem Canker Tolerance Frogeye Leaf Spot Aerial Web Blight Chloride Sensitivity Canopy Width 6 Shattering Plant Habit Ind Oil/Meal Type LLC;HLC; Seed Protein (% @ 13% 37.2 H20) Seed Oil (% @ 13% H20) 17.9 Seed Size Score 5 Flower Color W Pubescence Color T Hila Color G Pod Color BR Seed Coat Luster

TABLE 2 VARIETY COMPARISON DATA YIELD MATABS SPLB SDS Variety1 Variety2 Statistic bu/a 60# ABS count ABS count ABS score ABS XR28K10 92M61 Mean1 57.5 132.9 2892 7.5 XR28K10 92M61 Mean2 57.7 130.3 3065 5.3 XR28K10 92M61 #Locs 17 8 5 2 XR28K10 92M61 #Reps 34 17 5 4 XR28K10 92M61 #Years 1 1 1 1 XR28K10 92M61 % Wins 35.3 87.5 0 50 XR28K10 92M61 Diff −0.2 2.6 −173 2.3 XR28K10 92M61 SE Diff 1.17 0.8 23.7 2.25 XR28K10 92M61 Prob 0.8721 0.014 0.0019 0.5 XR28K10 92M91 Mean1 57.5 132.9 2892 7.5 XR28K10 92M91 Mean2 56.4 132.6 2889 7 XR28K10 92M91 #Locs 17 8 5 2 XR28K10 92M91 #Reps 34 17 5 4 XR28K10 92M91 #Years 1 1 1 1 XR28K10 92M91 % Wins 52.9 50 20 50 XR28K10 92M91 Diff 1.1 0.3 3 0.5 XR28K10 92M91 SE Diff 1.29 0.34 22.4 0.5 XR28K10 92M91 Prob 0.4224 0.3884 0.8892 0.5 XR28K10 92Y61 Mean1 57.5 132.9 2892 7.5 XR28K10 92Y61 Mean2 53.6 129 2905 5.8 XR28K10 92Y61 #Locs 17 8 5 2 XR28K10 92Y61 #Reps 34 17 5 4 XR28K10 92Y61 #Years 1 1 1 1 XR28K10 92Y61 % Wins 88.2 87.5 40 100 XR28K10 92Y61 Diff 3.9 3.9 −13 1.8 XR28K10 92Y61 SE Diff 0.9 0.67 88.4 1.25 XR28K10 92Y61 Prob 0.0005 0.0007 0.8878 0.3949 XR28K10 92Y70 Mean1 57.5 132.9 2892 7.5 XR28K10 92Y70 Mean2 57.6 129.8 2738 7 XR28K10 92Y70 #Locs 17 8 5 2 XR28K10 92Y70 #Reps 34 17 5 4 XR28K10 92Y70 #Years 1 1 1 1 XR28K10 92Y70 % Wins 47.1 100 100 50 XR28K10 92Y70 Diff −0.1 3.1 154 0.5 XR28K10 92Y70 SE Diff 1.17 0.39 37.4 0.5 XR28K10 92Y70 Prob 0.9256 0.0001 0.0146 0.5 XR28K10 92Y80 Mean1 56.7 131.6 2892 7.5 XR28K10 92Y80 Mean2 57.5 131 2809 6.5 XR28K10 92Y80 #Locs 22 10 5 2 XR28K10 92Y80 #Reps 39 19 5 4 XR28K10 92Y80 #Years 2 2 1 1 XR28K10 92Y80 % Wins 45.5 50 60 100 XR28K10 92Y80 Diff −0.9 0.6 82 1 XR28K10 92Y80 SE Diff 1.21 0.86 65.8 0.5 XR28K10 92Y80 Prob 0.4824 0.5009 0.2781 0.2952 PROTN OILPCT R160 R180 Variety1 Variety2 Statistic pct ABS pct ABS pct ABS pct ABS XR28K10 92M61 Mean1 35.81 17.48 6.31 4.82 XR28K10 92M61 Mean2 33.02 18.62 9.56 3.99 XR28K10 92M61 #Locs 10 10 9 9 XR28K10 92M61 #Reps 12 12 11 11 XR28K10 92M61 #Years 1 1 1 1 XR28K10 92M61 % Wins 100 0 100 0 XR28K10 92M61 Diff 2.79 −1.15 3.25 −0.83 XR28K10 92M61 SE Diff 0.323 0.165 0.26 0.194 XR28K10 92M61 Prob 0 0.0001 0 0.0028 XR28K10 92M91 Mean1 35.81 17.48 6.31 4.82 XR28K10 92M91 Mean2 32.31 18.91 10.12 5.09 XR28K10 92M91 #Locs 10 10 9 9 XR28K10 92M91 #Reps 11 11 11 11 XR28K10 92M91 #Years 1 1 1 1 XR28K10 92M91 % Wins 100 0 100 77.78 XR28K10 92M91 Diff 3.5 −1.43 3.81 0.28 XR28K10 92M91 SE Diff 0.225 0.151 0.161 0.17 XR28K10 92M91 Prob 0 0 0 0.1401 XR28K10 92Y61 Mean1 35.81 17.48 6.31 4.82 XR28K10 92Y61 Mean2 36.15 17.4 6.7 4.54 XR28K10 92Y61 #Locs 10 10 9 9 XR28K10 92Y61 #Reps 10 10 11 11 XR28K10 92Y61 #Years 1 1 1 1 XR28K10 92Y61 % Wins 30 60 88.89 22.22 XR28K10 92Y61 Diff −0.34 0.08 0.39 −0.27 XR28K10 92Y61 SE Diff 0.191 0.066 0.14 0.109 XR28K10 92Y61 Prob 0.1086 0.2792 0.0239 0.0371 XR28K10 92Y70 Mean1 35.81 17.48 6.31 4.82 XR28K10 92Y70 Mean2 33.22 17.85 10.13 4.57 XR28K10 92Y70 #Locs 10 10 9 9 XR28K10 92Y70 #Reps 11 11 11 11 XR28K10 92Y70 #Years 1 1 1 1 XR28K10 92Y70 % Wins 100 20 100 44.44 XR28K10 92Y70 Diff 2.58 −0.37 3.82 −0.25 XR28K10 92Y70 SE Diff 0.229 0.133 0.225 0.167 XR28K10 92Y70 Prob 0 0.0211 0 0.172 XR28K10 92Y80 Mean1 35.81 17.48 6.33 4.73 XR28K10 92Y80 Mean2 35.27 17.99 10.8 4.93 XR28K10 92Y80 #Locs 10 10 11 11 XR28K10 92Y80 #Reps 11 11 13 13 XR28K10 92Y80 #Years 1 1 2 2 XR28K10 92Y80 % Wins 90 10 100 81.82 XR28K10 92Y80 Diff 0.53 −0.52 4.48 0.2 XR28K10 92Y80 SE Diff 0.234 0.156 0.267 0.168 XR28K10 92Y80 Prob 0.0486 0.009 0 0.2715 R181 R182 R183 WHDFLD Variety1 Variety2 Statistic pct ABS pct ABS pct ABS score ABS XR28K10 92M61 Mean1 78.3 7.97 2.48 5 XR28K10 92M61 Mean2 22.13 55.96 8.25 4 XR28K10 92M61 #Locs 9 9 9 4 XR28K10 92M61 #Reps 11 11 11 9 XR28K10 92M61 #Years 1 1 1 1 XR28K10 92M61 % Wins 0 100 100 75 XR28K10 92M61 Diff −56.17 47.99 5.77 1 XR28K10 92M61 SE Diff 2.047 1.904 0.201 0.7 XR28K10 92M61 Prob 0 0 0 0.4318 XR28K10 92M91 Mean1 78.3 7.97 2.48 5 XR28K10 92M91 Mean2 22.79 54.18 7.69 5 XR28K10 92M91 #Locs 9 9 9 4 XR28K10 92M91 #Reps 11 11 11 9 XR28K10 92M91 #Years 1 1 1 1 XR28K10 92M91 % Wins 0 100 100 0 XR28K10 92M91 Diff −55.51 46.22 5.21 −1 XR28K10 92M91 SE Diff 1.552 1.392 0.116 0.2 XR28K10 92M91 Prob 0 0 0 0.0796 XR28K10 92Y61 Mean1 78.3 7.97 2.48 5 XR28K10 92Y61 Mean2 79.21 6.84 2.54 4 XR28K10 92Y61 #Locs 9 9 9 4 XR28K10 92Y61 #Reps 11 11 11 9 XR28K10 92Y61 #Years 1 1 1 1 XR28K10 92Y61 % Wins 55.56 44.44 66.67 75 XR28K10 92Y61 Diff 0.91 −1.12 0.07 1 XR28K10 92Y61 SE Diff 1.489 1.364 0.073 0.3 XR28K10 92Y61 Prob 0.5599 0.4346 0.3856 0.1253 XR28K10 92Y70 Mean1 78.3 7.97 2.48 5 XR28K10 92Y70 Mean2 22.71 54.1 8.4 3 XR28K10 92Y70 #Locs 9 9 9 5 XR28K10 92Y70 #Reps 11 11 11 10 XR28K10 92Y70 #Years 1 1 1 1 XR28K10 92Y70 % Wins 0 100 100 100 XR28K10 92Y70 Diff −55.59 46.13 5.92 2 XR28K10 92Y70 SE Diff 1.822 1.699 0.09 0.3 XR28K10 92Y70 Prob 0 0 0 0.0085 XR28K10 92Y80 Mean1 77.75 8.64 2.44 5 XR28K10 92Y80 Mean2 23.17 52.67 8.33 5 XR28K10 92Y80 #Locs 11 11 11 4 XR28K10 92Y80 #Reps 13 13 13 9 XR28K10 92Y80 #Years 2 2 2 1 XR28K10 92Y80 % Wins 0 100 100 50 XR28K10 92Y80 Diff −54.58 44.03 5.89 0 XR28K10 92Y80 SE Diff 1.914 1.698 0.08 0.1 XR28K10 92Y80 Prob 0 0 0 0.1817

TABLE 3 Soybean SSR Marker Set SAC1006 SATT129 SATT243 SATT334 SAC1611 SATT130 SATT247 SATT335 SAC1634 SATT131 SATT249 SATT336 SAC1677 SATT133 SATT250 SATT338 SAC1699 SATT142 SATT251 SATT339 SAC1701 SATT144 SATT255 SATT343 SAC1724 SATT146 SATT256 SATT346 SAT_084 SATT147 SATT257 SATT347 SAT_090 SATT150 SATT258 SATT348 SAT_104 SATT151 SATT259 SATT352 SAT_117 SATT153 SATT262 SATT353 SAT_142-DB SATT155 SATT263 SATT355 SAT_189 SATT156 SATT264 SATT356 SAT_222-DB SATT165 SATT265 SATT357 SAT_261 SATT166 SATT266 SATT358 SAT_270 SATT168 SATT267 SATT359 SAT_271-DB SATT172 SATT270 SATT361 SAT_273-DB SATT175 SATT272 SATT364 SAT_275-DB SATT181 SATT274 SATT367 SAT_299 SATT183 SATT279 SATT369 SAT_301 SATT186 SATT280 SATT373 SAT_311-DB SATT190 SATT282 SATT378 SAT_317 SATT191 SATT284 SATT380 SAT_319-DB SATT193 SATT285 SATT383 SAT_330-DB SATT195 SATT287 SATT385 SAT_331-DB SATT196 SATT292 SATT387 SAT_343 SATT197 SATT295 SATT389 SAT_351 SATT199 SATT299 SATT390 SAT_366 SATT202 SATT300 SATT391 SAT_381 SATT203 SATT307 SATT393 SATT040 SATT204 SATT314 SATT398 SATT042 SATT212 SATT319 SATT399 SATT050 SATT213 SATT321 SATT406 SATT092 SATT216 SATT322 SATT409 SATT102 SATT219 SATT326 SATT411 SATT108 SATT221 SATT327 SATT412 SATT109 SATT225 SATT328 SATT413 SATT111 SATT227 SATT330 SATT414 SATT115 SATT228 SATT331 SATT415 SATT122 SATT230 SATT332 SATT417 SATT127 SATT233 SATT333 SATT418 SATT420 SATT508 SATT583 SATT701 SATT421 SATT509 SATT584 SATT708-TB SATT422 SATT510 SATT586 SATT712 SATT423 SATT511 SATT587 SATT234 SATT429 SATT512 SATT590 SATT240 SATT431 SATT513 SATT591 SATT242 SATT432 SATT514 SATT594 SATT433 SATT515 SATT595 SATT436 SATT517 SATT596 SATT440 SATT519 SATT597 SATT441 SATT522 SATT598 SATT442 SATT523 SATT601 SATT444 SATT524 SATT602 SATT448 SATT526 SATT608 SATT451 SATT529 SATT613 SATT452 SATT533 SATT614 SATT454 SATT534 SATT617 SATT455 SATT536 SATT618 SATT457 SATT537 SATT628 SATT460 SATT540 SATT629 SATT461 SATT544 SATT630 SATT464 SATT545 SATT631 SATT466 SATT546 SATT632-TB SATT467 SATT548 SATT633 SATT469 SATT549 SATT634 SATT470 SATT550 SATT636 SATT471 SATT551 SATT640-TB SATT473 SATT552 SATT651 SATT475 SATT555 SATT654 SATT476 SATT556 SATT655-TB SATT477 SATT557 SATT656 SATT478 SATT558 SATT660 SATT479 SATT565 SATT661-TB SATT480 SATT566 SATT662 SATT487 SATT567 SATT665 SATT488 SATT568 SATT666 SATT491 SATT569 SATT667 SATT492 SATT570 SATT672 SATT493 SATT572 SATT675 SATT495 SATT573 SATT677 SATT497 SATT576 SATT678 SATT503 SATT578 SATT680 SATT506 SATT581 SATT684 SATT507 SATT582 SATT685

Breeding History

Variety XR28K10 evolved from a cross of 93M13 x SP11513488 as shown in Table 4.

TABLE 4 Phase Methodology crossing Bi-parental cross F1 Grow out of individual F1 plants to create F2 seed F2 Modified single seed descent F3 Modified single seed descent F4 Single plant selection for progeny row yield test F4:F5 Progeny row yield test R1 Yield Test Retest at multiple locations R1 Purification Single plant purification R2 Purification Plant Row Purification R2.5 Increase 1.25 acre Bulk purification increase R3 Yield Test Wide area testing R4 Yield Test Wide area testing

All publications, patents and patent applications mentioned in the specification are indicative of the level of those skilled in the art to which this invention pertains. All such publications, patents and patent applications are incorporated by reference herein for the purpose cited to the same extent as if each was specifically and individually indicated to be incorporated by reference herein.

The foregoing invention has been described in detail by way of illustration and example for purposes of clarity and understanding. As is readily apparent to one skilled in the art, the foregoing are only some of the methods and compositions that illustrate the embodiments of the foregoing invention. It will be apparent to those of ordinary skill in the art that variations, changes, modifications and alterations may be applied to the compositions and/or methods described herein without departing from the true spirit, concept and scope of the invention. 

1. A plant or plant part of soybean variety XR28K10, representative seed of said soybean variety XR28K10 having been deposited under ATCC Accession Number PTA-13150.
 2. A seed of soybean variety XR28K10, representative seed of said soybean variety XR28K10 having been deposited under ATCC Accession Number PTA-13150.
 3. A soybean seed obtained transforming the seed of claim 2 with a transgene.
 4. The seed of claim 3, wherein the transgene confers a trait selected from the group consisting of male sterility, site-specific recombination, abiotic stress tolerance, altered phosphorus, altered antioxidants, altered fatty acids, altered essential amino acids, altered carbohydrates, herbicide resistance, insect resistance and disease resistance.
 5. A soybean plant, or a part thereof, produced by growing the seed of claim
 2. 6. A tissue culture produced from the soybean variety of claim
 1. 7. A method for developing a second soybean plant, said method comprising applying plant breeding techniques to a first soybean plant, or parts thereof, wherein said first soybean plant is the soybean plant of claim 5, and wherein application of said techniques results in development of said second soybean plant.
 8. A method for producing soybean seed, said method comprising crossing two soybean plants and harvesting the resultant soybean seed, wherein at least one soybean plant is the soybean plant of claim
 5. 9. The soybean seed produced by the method of claim
 8. 10. A soybean plant, or a part thereof, produced by growing said seed of claim
 9. 11. A method for developing a second soybean plant in a soybean plant breeding program, said method comprising applying plant breeding techniques to a first soybean plant, or parts thereof, wherein said first soybean plant is the soybean plant of claim 10, and wherein application of said techniques results in development of said second soybean plant.
 12. A method of producing a soybean plant comprising a locus conversion, the method comprising introducing a locus conversion into the plant of claim 5, wherein said locus conversion provides a trait selected from the group consisting of male sterility, site-specific recombination, abiotic stress tolerance, altered phosphorus, altered antioxidants, altered fatty acids, altered essential amino acids, altered carbohydrates, herbicide resistance, insect resistance, and disease resistance.
 13. A herbicide resistant soybean plant produced by the method of claim
 12. 14. A disease resistant soybean plant produced by the method of claim
 12. 15. An insect resistant soybean plant produced by the method of claim
 12. 16. The soybean plant of claim 15, wherein the locus conversion comprises a transgene encoding a Bacillus thuringiensis (Bt) endotoxin.
 17. A soybean plant obtained by transforming the plant of claim 5 with a transgene.
 18. The plant of claim 17, wherein the transgene confers a trait selected from the group consisting of male sterility, site-specific recombination, abiotic stress tolerance, altered phosphorus, altered antioxidants, altered fatty acids, altered essential amino acids, altered carbohydrates, herbicide resistance, insect resistance, and disease resistance.
 19. A method for developing a second soybean plant, said method comprising applying plant breeding techniques to a first soybean plant, or parts thereof, wherein said first soybean plant is the soybean plant of claim 17, and wherein application of said techniques results in development of said second soybean plant.
 20. A soybean plant, or a part thereof, expressing all the physiological and morphological characteristics of soybean variety XR28K10, representative seed of said soybean variety XR28K10 having been deposited under ATCC Accession Number PTA-13150. 